OpenJSQ Help

Part 1 — Getting startedEverything a new operator needs, kept short. Each topic here has a longer section in Part 2.

1. What OpenJSQ is

OpenJSQ turns a radio and a sound card into a messaging station. If you can use a text-messaging app, you can use this — there are no protocol codes to memorize and nothing to type except what you want to say. All the protocol detail is still there when you want it — you just do not need any of it to make a contact.

Four things it does:

• Chat — conversations with other stations, group conversations, and relaying through a station that hears you both.
• Files — reliable file transfer that resumes if interrupted and re-sends only the pieces that were lost.
• Mail — leave a letter for a station that isn't on the air right now; your station delivers it automatically the next time they're heard.
• Network map — a live picture of who can hear whom, with real signal numbers on every path.

It speaks up to three radios. FSQ is a slow, very forgiving keyboard mode for HF — good on 80 and 40 meters, and fully compatible with stations running fldigi or FSQCall. AX1200 is classic 1200-baud VHF/UHF packet, and works with any FM rig. JG25 is OpenJSQ’s own FM waveform, faster than AX1200, and it appears only in a build compiled to offer it. Everything above — chat, files, mail, the map — works the same on all of them. That is the whole idea behind the program: the services are written once, and the radio underneath is just what carries them.

2. Getting ready: hardware, installing, and the beta licence

Everything in this section happens before the setup wizard, and it is the part that decides whether the wizard goes well. None of it takes long, but skipping it is why a first session usually stalls.

What you need

Setting the radio up, once

OpenJSQ cannot see any of these, and every one of them will look like a software fault if it is wrong.

Finding out which sound card is which

The wizard's sound-card page stops more first sessions than anything else, and the reason is always the same: the name in the list does not obviously belong to your interface. Two minutes now saves an evening later.

1. Unplug the interface. On Windows open Settings → System → Sound → All sound devices; on macOS, Audio MIDI Setup; on Linux, arecord -l. Note what is listed.
2. Plug it back in and look again. Whatever appeared is your interface — under whatever name the manufacturer chose. USB Audio CODEC, USB PnP Sound Device and DigiRig are all common; so is a rig's own name.
3. Write the name down. That exact string is what you pick in the wizard (Audio from radio and Audio to radio) and on the Radio page (Audio input (from radio) and Audio output (to radio)). Every entry is listed as Name (Host API) — on Windows, USB Audio CODEC (Windows DirectSound), say — because each card is offered through one host API only.
4. Turn Windows' own processing off for it. In that device's properties, disable Audio Enhancements and any exclusive mode setting. Windows adds effects to sound devices by default, and none of them help a modem.

If you plugged the interface in after starting OpenJSQ, press Refresh — the list is read once when the page opens.

Installing

• Windows. Unpack the ZIP you were sent somewhere you can write to — your Documents folder is fine — and run openjsq-desktop.exe. There is no installer and nothing is written to the registry. Everything the program needs travels in the folder.
• macOS and Linux. Build from source. You need Qt 6 (Widgets, Sql, Network, PrintSupport — neither Qt SerialPort nor Qt Bluetooth is used), PortAudio, CMake 3.24 or newer, and a C++20 compiler, then the usual cmake -S . -B build && cmake --build build. The desktop program is build/desktop/openjsq-desktop.
• Which build am I running? A closed-beta copy says so in its title bar — your callsign and the days remaining. A copy that is not gated says nothing there. Every copy carries this guide inside it: the Help button at the foot of the rail, or F1, opens it in your web browser.

The closed beta licence

Beta builds are licensed to one operator by callsign. This is not copy protection in the usual sense — it is so that a copy which turns up somewhere it should not can be traced back — but it does mean there is one file to put in place before the program will transmit.

1. You are sent a file called openjsq-beta-license.json.
2. Put it in the data folder, with that exact name. The full path is <data folder>/openjsq-beta-license.json.
3. Start OpenJSQ. If the licence is good you go straight to the program; the title bar picks up your callsign and a day count.

If it is not good, OpenJSQ says so once, at startup, in a dialog titled OpenJSQ Closed Beta — before the main window opens, rather than opening and then refusing everything. The dialog names the licence file's full path, and carries two buttons: Open Data Folder, which opens the folder the file belongs in, and Exit.

What each message means

Being warned before it runs out

OpenJSQ counts down whichever expires first, the licence or the build. The title bar always carries the count beside your callsign — N0CALL - 23 days left, with (build) added when it is the program that runs out; inside 7 days it also spells the warning out in a sentence; on the last day you also get a notice at startup. The wording always says which clock is running out, because the two need different answers: a licence expiring is a message to whoever issued it, a build expiring needs a new download.

Am I set up? — the checklist

Everything below can be checked without transmitting. Work down it before your first call, and again whenever something stops working.

Items 1 to 8 are all checkable in a shack with the antenna disconnected. Only 9 and 10 need the outside world.

Proving your transmitter, without bothering anybody

Steps 1 to 4 put no signal on the air at all.

1. Watch the software key. Press Tune on the Radio page with the radio switched off. Stop TX appears in the top bar and the status bar reads TX. That proves OpenJSQ's side.
2. Watch the radio key. Turn the radio on, into a dummy load, and press Tune again. The transmitter should come up. If it does not, this is PTT — see Decodes but won't transmit in section 21.
3. Set the level. Still into the dummy load: raise Drive until the rig shows the power you want with the ALC meter barely moving, then Stop tuning. On FM there is no ALC to watch — set drive so the deviation sounds like a normal voice on a second receiver, and no louder. Tune works only while FSQ is selected; on AX1200 and JG25 the button is greyed out, so switch to FSQ for the tone, or set the level on a short test message into the dummy load.
4. Hear yourself. Put any second receiver — a handheld, a web SDR, an SDR dongle — on your frequency and press Tune once more. Now you know what your signal sounds like, and that it is going somewhere.
5. Send something. Antenna on, an Allcall greeting on a live frequency. If nobody answers, that is normal — see below.

Where the people are

OpenJSQ does not pick frequencies for you, and this guide will not print a list that goes stale.

• On HF, FSQ activity has gathered by convention around 7.104 MHz and 3.588 MHz USB in North America. Treat those as a starting point, not gospel: check the FSQ and fldigi community pages, your regional digital-modes group, and — most usefully — ask on a net. FSQ is an NVIS mode above all, so the stations you can work are the ones a few hundred miles away, and 40 m by day / 80 m by night is the usual pattern.
• On VHF and UHF, pick a simplex data frequency and coordinate it with the people you want to talk to. There is no national OpenJSQ channel and inventing one would not help. Use your band plan's simplex segment, keep off the national calling channel, and if you share a channel with APRS, set Network profile → APRS coexistence so OpenJSQ behaves itself there.
• Patience is the mode. A quiet FSQ channel is not a fault. If the Channel page shows other people decoding, your receive side works and you are simply early.

When something is wrong: what to send

A screenshot of a symptom is rarely enough to find a radio problem. There is a built-in flight recorder, and it is worth turning on before you try to reproduce anything:

1. Open Channel, tick Show advanced settings at the top right, then tick Record diagnostics. It takes effect at once and needs no restart; the status bar carries a ● recording diagnostics reminder while it is on.
2. Make the problem happen.
3. Press Save bundle… and keep the ZIP.

The bundle holds the last ten minutes of receive audio exactly as the modem heard it, the decode history with offsets into that audio, and this station's configuration — which together answer nearly every “was it the radio or the software?” question. Send it with a sentence about what you expected and what happened instead.

3. First launch: the setup wizard

The first time you run OpenJSQ, a short wizard called Welcome to OpenJSQ walks you through setup. It is eight pages long — six if you tell it you use a KISS TNC, because two of them stop applying — and only one answer is truly required: your callsign. Everything else can be changed later on the Radio and Settings pages, and there's a Skip the rest button if you're in a hurry.

1. Your station — enter your Callsign (required — it identifies every transmission). Location and Status are optional; they're what your station answers when someone asks where you are or what's new.
   The callsign box is checked as you type, and Next stays disabled until it is a callsign: three to twenty characters, letters and digits. A packet SSID such as -7 does not go here — it is picked later, on the Radio page. The wizard says so in as many words rather than refusing silently.

   

   

2. Operating mode and connection — how OpenJSQ reaches your radio. FSQ using computer audio for HF keyboard work, AX1200 using computer audio to let OpenJSQ be the packet modem itself, AX1200 through an external KISS TNC if you already have one (Mobilinkd, Dire Wolf, a hardware TNC), JG25 using computer audio (experimental) where this build offers it, or Advanced or multi-kit setup — take me to the Radio page to finish here and go straight there. Don't agonize: you can switch any time on the Radio page, and section 16 compares the three waveforms properly.
   This choice decides what you are asked next. A TNC does its own modulation and keys the radio itself, so choosing it skips the sound-card and keying steps below — they are questions about hardware your station does not have.

   

   

3. Sound card — pick Audio from radio and Audio to radio. This step stops more first sessions than any other. Choose the interface wired to your radio (DigiRig, SignaLink, a USB rig's own sound device, or a virtual cable) — not the computer's own speakers and microphone. OpenJSQ tries to guess from device names and tells you when it has; check the guess, because a name is all it had to go on. Audio to radio also offers Receive only — never transmit.

   

4. Keying the transmitter — how the radio is told to transmit. VOX — the interface keys on audio needs no extra wiring, is what a SignaLink and other audio-operated interfaces use, and is the safe first choice. Serial line (RTS/DTR) keys a control line — a DigiRig, and most interfaces with a dedicated PTT lead; pick the serial port below it. Keying through CAT (flrig, rigctld, or a direct rig connection) is on the Radio page under advanced settings — OpenJSQ does not drive rigs itself, which is why there is no list of radio models in the wizard.
   The page also tells you the one thing this step does not settle: transmit drive starts at its quiet default, and you set it on the Radio page while watching the meter.

   

5. What your station does on its own — four services are on by default, and this is where you are told about them: Answer questions about this station (every radio), Carry other stations' messages (FSQ, JG25), Accept files and notes left for you, and Hold mail for stations that are not on air. The relay one names its radios because AX1200 forwarding is a separate switch on the Radio page. Every one of them transmits under your callsign. Leave them on to be a good neighbour, or turn any off here or later in Settings. The page closes with the escape hatch: Net mode in the top bar holds all four at once for a directed net, without changing these answers.
   Reached through the KISS TNC route this is page 3 of 6 rather than page 5 of 8 — the two pages above it were skipped — but the page itself is the same. A station that already has a callsign never walks the whole wizard again: when a later build adds a question it has not answered, a short version titled A few new questions opens at this page instead, and leaves every earlier answer where it was.

   

6. How it should look — choose Dark or Light, then Text size: Normal, Large, or Extra Large. Both apply immediately so you can judge them before leaving the wizard. Text size enlarges the text you read — messages, mail, channel traffic and the explanations on these pages; the meters, the navigation rail and the diagnostic cards keep their size, so nothing is pushed off the window.

   

7. Listen — the proof step. Press Start listening and watch the level bar — nothing is transmitted. When it moves, the page reports the actual level in dBFS and grades it: Too quiet — turn the radio up below −40 dBFS, Usable between −40 and −6, Clipping — turn the radio down above −6. That is the audio level and nothing more — it does not yet show that a message decodes, or that your transmitter is set up. If the bar stays flat for ten seconds the page says so itself and names the three usual causes — wrong input device, radio volume down, cable not seated.
   If you chose a KISS TNC there is nothing to listen to here: your TNC does its own receiving, and its port is set on the Radio page.

   

8. Before you start — what was set up, what was left alone, and what still needs doing. Transmit level is untested on every route, so it is named here rather than discovered on the air. The paragraph at the foot is the one worth reading twice: it spells out, in plain sentences, every transmission this station will make without being asked.

   

4. A quick tour of the window

The rail on the left is the whole navigation. There is no menu bar. Top to bottom:

The top bar runs left to right:

Short-lived notices also appear here when the station does something on its own — ✉ Transmitting: announcing held mail for N1ABC., ✉ Mail from N1ABC arrived — see Inbox., a shared file going out — so unattended work is never invisible. Where the window is narrow a notice shortens rather than pushing the bar around: ✉ ← N1ABC for mail arrived, ✉ ✓ N1ABC for mail delivered. Most fade after a few seconds; a held-mail announcement carries a Cancel send button while it goes out.

In a conversation, an unbroken run of automatic presence sends is collapsed into one quiet line — “Automatic presence ×6 · last 11:14” — so a station that has been sounding all afternoon does not bury the two sentences somebody actually typed.

Under the top bar sits the live spectrum strip. While receiving, it shows the audio and — on FSQ — the slot occupancy; the small slider at its right edge changes display sensitivity only. The slot chips live here now, each one sitting inside the band it describes — S1 ● when clear, S3 ● busy in amber, S3 ▲ TX in red for the slot you are transmitting on — with the frequency it listens on written in the band (1500 Hz · fldigi for the slot other FSQ programs use). Hovering a chip gives that slot's noise-floor numbers, which used to ride the top bar. AX1200 and JG25 have no slots — one channel carries everything — so on those the strip shows a single chip, AX ● or JG ●, that turns amber when the channel is busy and red with ▲ TX while you transmit; hovering it names the state in words (AX1200 packet channel clear). An RX or TX tag sits at the left of the trace. While the radio is stopped, the strip becomes useful rather than decorative: it says “Radio off — click to start listening”. If the missing callsign is the blocker, it reads “No callsign set — click to choose one” and takes you to Settings. The sensitivity slider is hidden while the radio is stopped.

The status bar at the bottom narrates what the station is doing (“Radio running.”, “TX · slot 3”), and says so plainly when something fails rather than leaving a button looking dead. The red TX always means your transmitter is keyed.

(Through an external KISS TNC that indication lags by the TNC's own delay — OpenJSQ knows when it handed the frame over, not when the transmitter actually came up.)

5. Quick start on HF — FSQ

Goal: from a working wizard to your first message in about five minutes.

1. Tune the radio. Set your rig to a known FSQ frequency in USB (data/USB-D if you have it) — e.g. 7.104 or 3.588 MHz are common FSQ gathering spots in North America. Frequency and mode are set on the radio itself.
2. Start the station. Press Start radio in the top bar (or the same button at the bottom of the Radio page). The footer reads “Running — 5 slots, monitoring all of them.” and the spectrum strip comes alive.
3. Check your receive level. The RX meter should move with band noise and hover comfortably above its floor — set your radio and interface levels so that on an empty channel the small slot chips in the spectrum strip stay quiet instead of flickering busy. (A slot is one of several sub-channels FSQ stations share inside one SSB channel — OpenJSQ listens to all of them at once).
4. Pick a mode. In the top bar's Mode box, start with FSQ-3 — it's the everyday speed and every FSQ program decodes it. (The four modes above the separator are the fldigi-compatible ones.)
5. Listen first. Stations appear on the Network page as they're decoded, and everything on frequency shows on Channel. A few minutes of watching tells you who's around.
6. Set your transmit level — once, carefully. On the Radio page, card Transmit level: Tune puts a real carrier on the air — use a dummy load or a clear frequency. Press Tune, raise Drive until your radio shows the power you want with the ALC meter barely moving, then press Stop tuning. FSQ puts out a steady, unvarying signal, so cranking for power buys you nothing — a clean signal with the ALC (automatic level control) meter barely moving beats a loud dirty one.
7. Say hello. On Chats, open the Allcall conversation (that's everyone on channel), type a greeting, press Enter. The message waits for a clear channel, then transmits — the footer under your bubble reads Queued, then Sending, then Sent. (Through a relay it reads Sent to relay instead, which is a smaller claim and an honest one.)
8. Nobody answers? That is normal — an FSQ channel can be quiet for hours, and silence is not a fault. Check the Channel page: if other stations are decoding there, your receive side works and you are simply early. If Channel is still empty after twenty minutes, try another frequency or another band. Section 21 covers the rest.
9. Talk to someone. Click a station on the Network page (double-click opens their chat), or press ＋ on Chats and type their callsign. Try Actions ▾ → Ask for a signal report — the reply comes back as a plain sentence telling you how they hear you: N1ABC heard you at 12 dB.

That is a working HF station. Section 8 covers everyday operating — the next section is only for VHF/UHF packet, and nothing in it is needed for FSQ.

6. Quick start on VHF — AX1200 packet

Goal: from a working wizard to your first packet message in about ten minutes, on 2 m or 70 cm.

1. Choose the technology. On the Radio page, card Radio & audio, set Radio technology to AX1200.
2. Set your packet address. AX.25 source shows your station callsign from Settings — it is not typed here — with an SSID list beside it. Leave it at No SSID, or pick one such as -7 for a handheld; the SSID distinguishes packet stations that use the same base call. If the callsign in Settings still carries an SSID of its own (an earlier build allowed it), the list is disabled until you remove it there.
3. Pick the radio link. Under Radio link:
   • Built-in modem (sound card) — OpenJSQ makes the 1200-baud audio itself and keys your FM rig exactly like the FSQ setup (same sound card and PTT settings).
   • Serial KISS TNC — for a radio with a TNC built in, such as a BTECH UV-PRO over Bluetooth. Three steps, in order:
     • In the radio: turn KISS TNC on and Digital Mode Enable off.
     • In Windows: pair the radio with the computer.
     • Here: pick the COM port — OpenJSQ offers the right one first — leave Speed at 9600, and press Connect.
     No sound card and no PTT wiring are used: the radio does all of it.
   • Network KISS TNC — for a TNC that is a program on the network rather than a device on a wire: Dire Wolf, a Raspberry Pi beside the radio, or a shared TNC elsewhere in the shack. Enter its Host (127.0.0.1 if it is on this computer) and TCP port, then Connect. Like the serial TNC, it modulates, listens to the channel, and keys the transmitter itself.
     The one Dire Wolf mistake everybody makes
     Point OpenJSQ at the KISS port, not the AGW port. Dire Wolf listens for KISS on its KISSPORT line — 8001 by default — while AGWPORT (8000) speaks a different protocol entirely. A station aimed at 8000 connects perfectly and then never passes a single frame.
4. Pick the channel profile. Network profile: use Dedicated OpenJSQ channel on your own simplex frequency. Choose APRS coexistence only if you must share an APRS channel — it politely disables files, relay, and automatic signal reports so you don't clutter the shared frequency.
5. Start. Press Start radio. The footer reads “Running AX1200 - packet channel active.”
6. Say hello. Chats works exactly as on FSQ. One packet-only extra: the Live / Verified chip next to the compose box. Live sends once; Verified gets acknowledged packet by packet and re-sends anything missing — pick Verified when the message matters and you're talking to one station.
7. Send a file. On Files, pick a recently heard station from Destination (or type another callsign), click the file field or folder button, then press Send file. Progress, retries, and the result all show in the table; a partial transfer is resumable rather than restarted from byte zero.

7. Quick start on VHF — JG25

Goal: a working JG25 station in about five minutes, given that AX1200 or FSQ already works on the same computer. If neither does, do section 6 first — the sound card and keying are the same hardware and the same settings, and it is much easier to debug those on a waveform other people can hear.

1. Both ends must be OpenJSQ, and the same build. This is the one requirement JG25 adds and it is not negotiable: no other program decodes this waveform, and the wire format is not frozen between beta builds. Agree with the other operator on a frequency and on which build you are both running before you start.
2. Choose the waveform. Radio page, card Radio & audio, set Radio technology to JG25 — the third button on the row, in a build that offers it. Switching while the radio is running asks first, then restarts cleanly. The AX1200 panel disappears and the JG25 one takes its place.
3. There is no packet address to set. Unlike AX1200, JG25 identifies your station by your callsign alone — the one in Settings → Station. Nothing else to fill in.
4. Leave the sample rate at 48000 Hz. The JG25 modem works at 48 kHz internally; matching the sound card to it avoids a resampling step for no benefit.
5. Leave Mode and Error correction alone to begin with. A new station starts at JG25-FM 2400 with F0 — the fastest mode and no error correction, which is what JG25 was measured and validated at. Both settings describe what you transmit and nothing else — every frame carries a protected header naming the speed and coding it used, so the far station follows you automatically and the two of you never have to agree in advance. Change either later, on the top bar, when the path tells you to.
6. Start. Press Start radio. The spectrum strip shows a single chip — JG25 has no slots, one channel carries everything — reading packet channel clear, packet channel busy or packet transmitter active.
7. Say hello. Chats works exactly as it does on the other two. The Live / Verified chip is there as on AX1200: Verified when the message matters and you are talking to one station.
8. Send a file. As on AX1200 — Files, pick the destination, choose the file, Send file. Whole-file verification and resume both work.

If it does not decode

JG25's four tones span almost the entire audio passband, which makes it fussier about the audio path than AX1200 is. In order:

1. Turn the radio's processing off. Speech processor, noise blanker, DSP noise reduction, any “clarity” or “enhance” feature. All of them reshape the audio the demodulator is measuring.
2. Use wide FM if you have the choice. Narrow (12.5 kHz) FM clips the top of the passband, which is where JG25's fastest tones live.
3. Leave Adaptive receive equalization on. It is on by default and it exists precisely because FM audio is not flat and the tilt differs from radio to radio. Turn it off only to compare against a path you know is flat.
4. Drop a mode. A slower mode gets through where a faster one does not decode at all. Robust acquisition, a longer preamble, helps a receiver find a weak or fading signal in any mode.
5. Raise the error correction. F3 spends the most airtime and survives the most damage.
6. Check drive. Over-deviating on FM does not sound like distortion the way an overdriven SSB signal does; it just stops decoding. Set it by ear on a second receiver against a normal voice signal.

8. Everyday operating

Sending a message

Open a conversation, type, press Enter. That's the whole procedure. Under the box, a note line tells you what is about to happen. Messages wait for a clear channel before they transmit, so you can always change your mind: press ⦸ on its bubble (Cancel — take this back before the radio keys). Once the radio has keyed, it is too late, and OpenJSQ says so.

Knowing what happened to it

Every sent message carries its delivery state underneath. The words are chosen carefully: OpenJSQ never claims more than it can actually prove, so a weaker-sounding state is usually the honest one rather than a fault.

The state word sits after the time and the mode — 18:34 | FSQ-3 | Sent — in amber while the message is on its way and green once it is Sent or Delivered.

Section 9 has the full journey line for a relayed message, and section 10 the grades OpenJSQ gives to everything it receives.

Talking to stations that are not running OpenJSQ

Plenty of the program works with people who have never heard of it, and it is worth knowing which half is which before you wonder why a feature seems to be ignored.

On JG25 the answer is simpler: nobody. It is OpenJSQ's own waveform and no other program speaks it — which is the whole trade described in section 16.

Knowing whether a station is workable

Two kinds of evidence answer different questions. When the radio link can measure it, the SNR under a message describes how that one copy arrived. On FSQ, hover the footer for the decode margin — how much signal you had to spare over the mode's decode threshold — and the footer itself adds low margin N dB when there was less than 6 dB, because the next fade will lose you. Link Quality instead summarizes how reliably that station's recent traffic has decoded.

Asking things politely

The Actions ▾ button in any single-station chat turns the classic FSQ queries into plain clicks: signal report, location, what's-new, heard list, software version, wake, repeat, shared files, and more. Each radio action loads the compose box and nothing transmits until you press Enter; Esc cancels. Station info… is different: it opens the local station panel and transmits nothing. In a group conversation the menu offers one question only, Ask for a signal report — see Groups in section 9.

When mail arrives

The rail shows Inbox ●1 and the chat notes “Mail from them arrived — see Inbox.” Open the Inbox, read, done. To leave someone a letter for later, use Inbox → New mail… — your station holds it, announces it once straight away, and keeps trying when they are next heard.

Staying a good neighbor

• Automatic work is narrated: replies appear in the stream, while mail/presence/file-service activity also surfaces in status or top-bar activity text. ■ Stop TX is the emergency stop for queued OpenJSQ transmissions. On a KISS TNC, a frame the TNC already accepted may still transmit — at that point only the radio/TNC can stop RF.
• Net mode is the one-click “hold automatic traffic” switch for a directed net. It pauses presence/soundings, automatic query replies, and held-mail delivery on every radio while leaving messages you deliberately type and send untouched. It resets off when OpenJSQ restarts. The button shows its state — amber, reading Net mode ON — so a silenced station is recognisable at a glance. Turning it off tells you if something else is still holding transmit, such as a licence problem: you will see “Net mode off, but this station still cannot transmit…” rather than a claim that everything has resumed.
• Stick to the four classic modes (FSQ-2 … FSQ-6) when fldigi/FSQCall stations are on channel — those are the ones they decode. OpenJSQ never sends a fast mode at a station that has not advertised that capability.
• Map network transmits real heard-list queries. It runs only when you press it and can be stopped mid-crawl.

Part 2 — Going furtherThe complete reference: every page in depth, plus how the station decides what to trust.

9. Chats in depth ↑ contents

The conversation list

Conversations appear for: Allcall (always present — it's the whole channel), every group you're subscribed to, stations you've added by hand, every station in your heard list, and anyone you have history with. Each row shows the callsign, an unread dot, a ✉ badge when they've left unread mail, the slot and signal they were last heard on, and a preview of the last message. A reception still coming in previews live, marked ▸, character by character, as it decodes.

Press ＋ (or right-click → New conversation…) to start one. You do not have to have heard a station first — FSQ lets you call a station before it sounds. Type a callsign (portable suffixes work on FSQ; AX1200 uses the AX.25 callsign/SSID form), or a group name starting with @ or # — typing a group here also joins it.

Finding old traffic and inspecting a station

Search chats (Ctrl+F) searches more than the preview you can see: it digs into everything that station has ever sent you, pulls the conversation up, and then narrows the open thread to the matching lines. Clear the box to return to the ordinary conversation list.

Click the callsign in an open conversation, or choose Actions ▾ → Station info…, for a non-modal card titled Station N1ABC with what OpenJSQ actually knows: whether they are on the channel now, first and last heard, last and best SNR, the last mode, whether their callsign checksum has been verified (FSQ), how many messages you have exchanged, and Link Quality. Missing evidence is shown as a dash rather than invented as zero.

Groups

A group is a shared address several stations listen to at once — @ARES, #SKYWARN. Joining is as simple as starting a conversation with the group's name, or listing it under Radio → Groups → Subscribed groups. One list serves every radio. Group traffic is broadcast: delivery is always Live, and 📎 Files is unavailable.

The Actions ▾ menu in a group offers one thing, Ask for a signal report; everything else is greyed with the reason. Every member whose station answers group questions replies after its own short delay, so the answers do not collide, and the answers are filed in the group's conversation — N1ABC heard you at 14 dB — while your question's footer counts them: 1 station answered, 3 stations answered. Because each question costs the channel an answer from every member, you may ask the same group once every 5 minutes by default; inside that time the menu row reads Ask for a signal report — again in 3 min. Both halves live in Settings → Automatic replies: Limit group signal report requests to one per group every (No limit, 1, 2, 5, 10, 15 or 30 minutes) for asking, and Answer group signal report requests (Automatically by default, and only while automatic answers are on) for whether your own station replies.

The conversation header

Above the thread, on the right, sit three controls and one piece of evidence.

• Route: Direct ▾ — who carries your traffic to this station. Covered under Relaying through another station below.
• 📎 Files ▾ — two entries that name the station, Send N1TSB a file… and Browse N1TSB's files. Both hand off to the Files page with this station already filled in; the browse then asks over the radio from there, on the one request path the program has. This is the same pair of verbs a row in the Network page's Stations heard list offers on a right-click.
• Actions ▾ — the classic FSQ queries, itemised below.
• Beside the callsign, the meta line carries what is known about this station: signal, when they were last heard, their capabilities, the Link Quality badge — and, when there is evidence for it, Shares files.

The compose row, left to right

• The Route chip lives in the header above, not here — but it governs what the compose box does. When a route is set, the note line under the box always says where the traffic is going and by whose hand.
• Slot chip (FSQ) — which slot your messages go out on, e.g. Auto · Slot 1 (1500). Auto is right almost always: it follows the conversation and steps aside when a slot goes busy. For Allcall, Auto uses the fldigi slot so every program hears you. You can pin a slot from the chip's menu; the menu marks which choice non-OpenJSQ stations can hear.
• Delivery chip (AX1200 and JG25) — Live (sent once; the only choice for Allcall and groups) or Verified (acknowledged packet-by-packet with automatic re-sends; single stations only). Remembered per conversation.
• The text box — type and press Enter. ↑/↓ recall messages you've sent before; Esc cancels an armed action.
• Send — the button relabels itself to match what's loaded: Ask, Alert, Browse, or Transmit.

A long conversation does not draw itself all at once. The newest 200 lines appear immediately and a bar above the thread says how many are still behind them — “1,340 earlier lines in this conversation are not drawn yet.” — with a Show 200 more button beside it. Nothing has been lost or trimmed; only the drawing is deferred, which is what keeps a two-year conversation from taking a visible moment to open.

The note line under the box is the app thinking out loud: what the message will do, what it costs (on AX1200: bytes, packets, and airtime), and any problem with it — before anything transmits.

The Actions menu, item by item

Open a single-station chat and press Actions ▾. As the menu itself says: each of these loads the box below — nothing goes on the air until you press Enter.

Grayed items explain themselves — hover for the reason (station doesn't support it, radio not running, APRS profile, and so on).

Relaying through another station

When a station is beyond your reach, you send through one that hears you both. The station in the middle retransmits your traffic; the recipient sees it as coming from you, tagged via whoever carried it.

The Route chip

In the header of any single-station conversation, beside Actions ▾, sits a chip reading Route: Direct ▾. Click it and you get Direct, then one via … entry for every station you have heard — hover an entry for that relay's link quality, so you are choosing on evidence rather than hope. Pick one and the chip becomes Route: via K4ABC ▾.

That route then stays set for that conversation until you change it. It is not a one-shot decision per message, which is the point: if a correspondent is only reachable through a relay, that is a property of the path, not of one sentence you happened to type. The route is per conversation and is forgotten when you restart — it never silently persists into a session where propagation has changed.

The chip does not appear on Allcall or a group. Everyone hearing a broadcast has already heard it.

What travels the route

Once a route is set, it carries almost everything you do in that conversation — ordinary messages, the questions on the Actions menu, alerts, and mailbox notes. A route and an armed action work together rather than cancelling each other: arm Ask for a signal report, and the note line reads the whole plan back to you before you press Enter. Under the compose box you will see ↗ Goes to K4ABC, who passes it to N0XYZ — the route in English, never in punctuation.

Longer chains

The chip offers one hop, because one hop is what almost everyone needs, and it never offers the recipient as their own relay. For a longer route, type it: VIA1;VIA2;DEST your message — each hop separated by a semicolon, destination last. FSQ will carry a chain; AX1200 and JG25 pass traffic through one relay only and refuse a longer route rather than quietly truncating it.

Every hop is a separate transmission, so a chain is slow, and every station in it has to be listening and willing to relay. The note line warns you about any hop you have not actually heard.

Routes the app will not let you send

Each of these is refused with the reason in the note line, never silently downgraded to a direct send:

• Relaying through yourself.
• A route that ends back at you.
• The same station appearing twice — it can only pass a message on once, so the chain would stop there.
• More than one hop on AX1200 or JG25.

What a relay can and cannot carry

Mailbox notes (the # convention)

Typing #your note in a chat stores the note in that station's mailbox instead of their chat window — they read it later from their Inbox, even if they weren't listening when you sent it. #[name.txt] your note gives it a file name. This is the classic FSQ store mechanism, so it works with fldigi stations too.

ICS-213 forms

Actions ▾ → Send an ICS-213 form… opens a fill-in sheet mirroring the paper form: To, From, Subject, Message, Signature; date and time are stamped automatically in UTC. A box at the foot, File it in their mailbox, so they send back a receipt, is ticked by default, and the button reads Send form. Like every other action, Send form transmits nothing by itself: it loads the compose box — N1TSB#[ics213-n1tsa-2609152129.txt], the form filed under a name your station derives — and the note line says ICS-213 for N1TSB is ready — press Enter to transmit it. The byte counter now explains the transport rather than simply refusing a large form: a short form rides directly, while a form that exceeds the short-message budget is carried by the JSQ file service. At the far end it still opens as an ICS-213 form in the conversation/Inbox, and the underlying transfer remains visible on Files. Short labeled-text forms remain readable by classic FSQ software.

Deleting

Use a message's ✕ button (Delete this message); delete a whole conversation from its header's 🗑 or the list's right-click menu. Everything goes to the Deleted page, where it waits 30 days and can be restored with one click (Restore puts it right back; restored files never overwrite — a name clash becomes name (restored).ext).

10. Reading what arrives ↑ contents

Chats told you how to hold a conversation. This section is about reading one: the numbers under each message, the badge beside a callsign, and how much the program is willing to vouch for any of it. It is the part of OpenJSQ an operator grows into, and none of it needs a setting changed.

The footer under every message

Every bubble carries a footer line, and it is worth learning to read — it answers most of what you want to know about a contact without going anywhere else. On a received message the fields are, in this order, separated by bars — 18:28 | SNR 29 dB | 100% | FSQ-3 | slot 2 | 4.8 ch/s (58 wpm):

After those, a received footer adds notes only when they happen: via N1ABC on a relayed message, naming the station that actually handed it over; on AX1200, FEC recovered, 3/5 packets or live partial, missing packet, gap repaired, and APRS when it arrived under APRS coexistence; the outcome of a station action; low margin -2 dB on FSQ when there was little to spare; and no CRC on an FSQ message that carried no checksum.

A sent bubble is shorter — time, mode, slot where there is one, and the delivery state from section 8: 18:34 | FSQ-3 | Sent. There is nothing to measure on something you sent. Its notes say what else is known: answered or 2 stations answered on a question; sent automatically, automatic presence, carried for another station or mailbox service when a service rather than you sent it; 12/15 packets on a multi-packet AX1200 send; the relay journey below; and relayed for N1ABC.

Following a relayed message on its way

A message you sent through a relay carries a short journey line that fills in as evidence arrives:

Messages sent before this tracking existed simply say so rather than pretending to be unconfirmed. And when evidence could plausibly belong to more than one pending relayed message, it promotes neither — an ambiguous match leaves both unconfirmed rather than crediting the wrong one.

The Link Quality badge

Where a station has enough scored receptions, you will see a colored percentage such as 92%. That is Link Quality: how reliably this station's recent transmissions have actually decoded here. Signal strength is the physics when it is measurable; Link Quality is the outcome history.

The number is always inside the badge, so color is never the only signal. You will see Link Quality in chats, the open-conversation header, incoming bubbles, the Station info panel, and the Network page's Link column. It is tracked on FSQ, AX1200 and JG25 and survives a radio restart. A dash means OpenJSQ does not yet have enough evidence to claim a score.

Who you are talking to (AX1200)

The header of an AX1200 conversation says what the other station can receive. Before anything has been exchanged it reads what they can receive is learned from the first file, station action or confirmed chat exchanged with them; once they have answered, it says so in plain words — can receive delivery-confirmed chat, files, station actions and group messages, with relays for others added when they do. A station that offers none of the extras reads receives plain chat only — a real answer, and deliberately worded differently from "not asked yet." What was learned is kept across a restart and dated, (as of Sep 11 19:57). This is why grayed items in the Actions menu are grayed: the other end has told you what it can do.

How much OpenJSQ will vouch for it

Sometimes a banner replaces the ordinary footer, and it is worth knowing why. Weak-signal decoding means occasionally receiving a message almost perfectly. Most software silently guesses at the rest. OpenJSQ grades instead, and shows you the grade:

That table grades one message. The Link Quality badge grades a station — how reliably its recent traffic has decoded here — and the two are deliberately separate: a perfectly checked message from a station you have mostly been missing is still a checked message, and OpenJSQ will not average the two into a single reassuring number.

The Receive effort setting moves how much marginal text you see, but never what the station trusts — an unverified message stays unverified at every setting. Where OpenJSQ has a valid signal measurement, it normalizes SNR into the same 3 kHz reference so values are comparable across native radios. A KISS TNC that supplies no SNR is shown as unknown, not zero. OpenJSQ tells you when it has done something on its own; nothing happens off-screen.

11. Sending and receiving files ↑ contents

The Files page is the whole file service for every waveform — sending, another station's files, the folder you share, and the log of what you were asked for, in that order down the page. Under the title and its one-line description sit the three commands, then the Send a file card, then the transfer ledger. To send, choose a recently heard station from the editable station list (its placeholder reads Destination, e.g. N1RX-7), or type a callsign, click anywhere in the Choose a file field or its folder button, then press Send file. A zero-byte file is refused up front — there is nothing to send.

Each row has its own checkbox. Tick one or several rows, then use the action bar. The table shows direction, station, mode, file, size, Progress, rate, retries, state, and location. Progress counts blocks: 12 / 40 is what the receiver has confirmed, and an outgoing transfer that is ahead of its acknowledgements reads 16 / 40 sent · 12 confirmed. Being ahead is normal: the sender fills its window and only then asks. Hover the cell for the difference — blocks sent are not blocks delivered. Rate is measured by each station on its own clock, so the two ends of one transfer can differ slightly; Retries is counted by the sender and left blank on an incoming row. States include Queued Waiting Sending / Receiving Confirming Retrying Verified Failed Cancelled Paused. Confirming means every block is acknowledged and the whole-file verdict is still to come. Verified means the end-to-end file check completed successfully.

• Pause, Resume, and Cancel apply to the checked outgoing transfers. Pause/cancel recall work that has not yet gone on air; a frame already transmitting is allowed to finish at the next safe protocol boundary.
• Interrupted and idle transfers keep durable partial data so they can resume by asking for what is missing instead of starting over. A stalled incoming transfer stops holding a live channel after about ten minutes, but the part that already arrived is kept, so it can pick up where it left off.
• Delete entry removes finished history rows, not the file on disk. Open folder opens the unique folders represented by the checked rows.
• All newly received files — FSQ or AX1200 — land in the same incoming folder for the active profile. Old FSQ and AX1200 folders are intentionally left where they were after an upgrade; OpenJSQ shows a one-time notice so you know where those older files remain.

How it works underneath. JSQ File ARQ sends blocks, polls the receiver for the missing set, and retransmits only what still needs to arrive. On slow FSQ modes OpenJSQ sizes DATA blocks by airtime rather than forcing one enormous fixed block; if a transfer stops making progress it drops to smaller blocks and tries again — still the same transfer, so mail and resumption never lose track of it. The whole-file check is the final authority, not the number of apparently successful blocks.

The action bar: three verbs

Everything about files is on this one page now. Send a file… opens the file picker for the Send a file card just below. Browse files jumps to Browse a station. Share files reads Share files: Off, or Share files: On · 6 files, and scrolls you to your own sharing section. Nothing on the action bar transmits.

Sharing a folder of your own

Off by default, and the first thing you see is an invitation rather than a switch:

How sharing works spells out the whole contract before you commit to anything: you choose one folder; a station that has heard you can ask for the list of what is in it, and then ask for one file by its number in that list; your station answers only stations you allow, only files inside that folder, only up to the size and daily limits, and — if you choose Ask me first — only after you say yes.

Pick a folder and the invitation is replaced by the section that owns every sharing decision:

Under those, two lines the folder itself writes: a warning for every file the size ceiling would refuse, named individually so you can act on it before anybody asks, and the count — “6 files offered from this folder.”, or “Sharing is off — nothing is offered.” Changes apply at once; there is no Save button and no restart.

Browsing another station's files

1. Choose the station. Type a callsign or pick one you have heard. Three doors lead here with the station already filled in: Actions ▾ → Browse their files…, 📎 Files ▾ → Browse their files in the chat header, and a right-click on a row in Network → Stations heard.
2. Browse shows the list if this session already has it, and otherwise asks for it over the radio. Refresh always asks again. The distinction matters: one costs nothing, the other costs airtime and their rate-limit budget. The asking is visible in that station's conversation too — Asked to browse their shared files, then Asked to download shared file #3, each with its delivery state, and Download complete: shelter-roster.csv when the file lands.
3. The status line says how old the list is — “Last listing 14:07 · 5 files” — and adds a warning of its own once the station has not been heard for six hours or more: “list may be old — K4ABC has not been heard for 7 h”.
4. Pick a row and press Download (or double-click it). The State column then tracks that entry — Requested 14:09, Downloading…, Downloaded 14:16, or a refusal — while the file itself arrives in the transfer table at the top of the page like any other transfer.

Why you pick by number and never by name. The download carries the row's position in the listing plus a short fingerprint of that entry, never a filename. A filename is a path, and a path is something that can be pointed outside the shared folder; a row number cannot. The fingerprint is what makes a changed folder come back as “refused: their files changed since you listed them — ask for the list again” instead of quietly sending you the wrong file.

Answers you may get instead of a file

A refusal is a sentence, not a silence, and most of them are ordinary. The same words reach you whichever waveform carried the request — FSQ has no status byte and answers in short text, AX1200 and JG25 carry a code, and both are translated into one vocabulary before you see them.

Sharing activity: what your station was asked for

This is monitoring, not correspondence: your station working for somebody else, so it belongs beside the files rather than in Chats. The header counts today's requests; the table gives the time, the station, what was asked for ((file list) or a filename), and the answer your station gave, in this end's words — served — 14336 B, refused: asking too often, refused: not offered, refused: too large, refused: budget spent, waiting for you — while the far operator sees the same decision in the vocabulary of section 11's refusal table. It is cleared when the application restarts.

The technical limits, in Settings

Under Settings → Shared files, with Show advanced settings ticked:

12. Mail: letters that wait ↑ contents

Mail exists for one situation: the other station is not on the air right now. Your station takes custody of the letter and handles delivery itself.

Writing a letter

1. Inbox → New mail…
2. To: the recipient. Leave with: normally This station (deliver it yourself) — or pick a mailbox station that's on the air more than you are, and it will carry the letter for you (it must have custody enabled; if it declines, your station keeps the letter).
3. Write the letter and press Send when your own station will carry it. If you chose a third-party custodian, the button instead says Leave with <CALLSIGN> so the custody choice is explicit. The live counter is in bytes, not characters.

One announcement goes out straight away, heard or not — you just pressed send, and the worst case is one unanswered call. A small notice says so as the dialog closes: Held for N1ABC, and announced now. If they do not answer, it waits until they are heard — leave the radio running, and watch Holding for its progress. From then on it's automatic: when the recipient is next heard — even from a routine sounding — your station announces the letter again, they fetch it, and their confirmation releases it. Leave the radio running and watch Holding for progress.

If nothing goes out at all, the activity line says which hold is stopping it — “Held for N1ABC. Net mode is on, so nothing goes out automatically.”, or “Held for N1ABC. Not transmitting: …” for a licence or transmit problem — rather than reporting that the letter is on its way.

Short letters and long ones

A letter that fits in one frame rides inside the mail message itself. A longer one is not refused — the recipient is sent a short notice and the text follows automatically as a file transfer. You are told which is happening before you commit, because the second costs a negotiated transfer on the air and the first does not.

Past 256 KB the letter is refused with the reason, and the dialog points you at the Files page — which is what the recipient would have received either way. Letters left with a mailbox station work the same: an oversize deposit carries a referral and the custodian passes the file along.

Letters that arrive as a file

A letter too long for one frame travels as a file — the bench letter above did, at 288 bytes on JG25 — and still arrives as ordinary text in your Inbox, read back from the transfer once it is verified. A letter whose body is a file, on the other hand (a file handed on through a relay as a letter, say), shows in your Inbox as Attachment: name (n KB) rather than as body text. The file is kept exactly as it was sent, byte for byte — nothing is decoded, trimmed or tidied on the way in, because a letter that was acknowledged as delivered and then quietly altered would be worse than one that failed. The name is derived by your own station, never taken from the sender: a filename chosen by a remote station is a path supplied by a stranger.

The same rule constrains what you can send this way. A file relayed as a letter body has to be genuine text that survives the round trip — an empty file, one containing binary data, or one that is not valid UTF-8 is refused up front with the reason, rather than being carried and arriving as mush.

Finding, filing, replying, and steering delivery

• Search mail — inbox, sent and folders searches both sides of the ledger at once: sender/recipient, body, carrying station, and your folder labels.
• Inbox and Sent are joined by user folders. Right-click a letter to move it into an existing folder, create a new one, or return it to Inbox. A folder is a label on living mail; filing a letter does not silently mark it read.
• Reply follows the kind of message you received. A short classic # mailbox note routes the reply back to Chat. A letter created in Inbox opens a mail compose window carrying Include the previous conversation below — ticked by default, and it quotes the original under a divider the way email does. Watch the byte counter as you toggle it: a quote can be what pushes a reply past the inline limit and turns it into a file transfer.
• Check mail… asks another station whether it is holding mail for you. Whatever they are holding for you comes across the same way as any other letter.
• Holding — a toolbar button that reads Holding (2) while letters are held — opens a window of the letters this station is carrying, with who each is for, its status, tries, when it was last announced and when it expires. Send now deliberately resets that letter's normal retry budget and makes a real new attempt. Give up letter stops carrying it, after asking. View letter opens it, and Show finished letters brings back the ones already delivered or given up. The window can stay open while you work.
• Save…, Delete, Mark unread, and Mark all read behave like their mail-program counterparts. On a narrow screen the Inbox actions wrap onto a second row rather than being clipped or hidden, so every one of them stays reachable.

Being a community mailbox

Settings → Mail → Hold letters for other stations (on by default) lets other stations deposit letters with you for third parties — a store-and-forward network needs stations willing to carry mail. Your own letters are always held by your own station regardless.

13. The Network page: mapping who hears whom ↑ contents

The right-hand STATIONS HEARD list is your receiver's memory. Its columns are Station, Signal, Link, and Heard. Signal is calibrated SNR when the active modem/TNC actually supplies a valid measurement; an external KISS path that cannot report SNR shows -- dB rather than a made-up 0 dB. Link is the recent decode-success score and is independent of signal strength. Double-click a row to open that station's chat.

The graph is the bigger picture. Arrows point at the station doing the hearing — A ⟶ B means B hears A. Blue straight arrows are first-hand paths: what your receiver heard, a station's own report about hearing you, or — drawn with -- and no number — a station whose traffic proves it decoded you, because it acknowledged your message, answered your request, replied to your file transfer, relayed your message on, or took custody of your letter (hover the leg and it says which); green curved arrows are hearsay from one remote station about another. Edge labels show dB when a valid SNR exists, 40+ dB above the measurable range, and -- dB when nothing was measured. Wheel zooms, drag pans, +/−/fit on the toolbar, and hovering an edge explains who heard whom and when.

Mapping beyond your horizon

Press Map network. Your station asks each neighbor who they hear and draws the combined graph. The same station-action dispatch is used on FSQ, built-in AX1200, and KISS AX1200; if a request cannot actually be queued, the crawl skips it with the refusal reason instead of pretending it waited for a remote timeout. The button becomes Stop mapping; stopping keeps partial results.

Reset clears the topology picture and the RELAY ACTIVITY table below it — not your heard list, and not any history. Switching profiles also clears the old profile's graph so a plausible-looking map from the shack cannot leak into a field profile.

What a Stations heard row can tell you about files

A station that has given evidence of sharing carries a Shares files badge beside its callsign in Stations heard, with a small network icon — the same badge the chat header and the Files pickers show, from the same single record. No evidence means no badge, never a grey “unknown”: the program does not report a station as not sharing merely because it has not been told. Right-click any row for Open chat, Browse their files and Send … a file… — the same verbs as the chat header, and browsing a station with no badge is allowed, because that is how you find out.

Relay activity: what you carried for other people

Below the map, RELAY ACTIVITY lists the traffic your station has passed along for others. This is service work, not conversation — none of it ever appears in Chats or in an unread count, which is exactly right: being a relay should not fill your inbox with other people's mail.

Six columns: From (the station that wrote it), To (where it was going), Carried (what was relayed — on AX1200 a sentence naming the kind, Relayed a message for N1ABC, or file traffic, a station action, a control frame; on FSQ the text that was passed along), Heard, Passed on, and State. States run waiting for the channel → transmitting → passed on, with retrying, failed and cancelled where they apply. A row reading not passed on means your station heard the request and did not retransmit it — relaying switched off, or the traffic was a duplicate or a loop.

What the map answers in practice: who would make a good net control (everyone hears them), which paths are one-way (A hears B at +12 while B hears A at +2 — perfectly normal on HF, and exactly what you need to know), and who is only reachable via which relay.

14. The Channel page: everything your receiver hears ↑ contents

Chats shows conversations; Channel shows the channel — every slot, every decode, addressed to you or not, plus the evidence behind every decision. You never need this page to operate. You'll want it anyway.

The page has two views. Basic, the everyday one, answers “what came and went?”. Its colour key is received, checked · needs your eye · sent by you · damaged, and its history has four columns: Time, Station (N1ABC → you, you → everyone), Message in plain words (N1ABC heard you at 29 dB, file block 12, 102 bytes, mail announcement), and Result — Received, Sent, Needs your eye, Damaged, Unreadable, Presence or Local note. A frame heard but not readable at all is listed as Signal heard, message unreadable. The filters are All, Received, Sent and Damaged. Selecting a row shows a short card — who, when, which radio and mode, then Result, Signal, Kind and Length — with Open chat with N1ABC › (Open in Chats › where the row names no station) and Show diagnostics ›. Keep history and Clear all are in both views, and so — on FSQ — is the Monitor squelch box beside the filters, which sets how strong a signal the live decoder cards react to and changes nothing about what is decoded.

Show advanced settings, at the top right, turns the same page into the evidence view the rest of this list describes. On FSQ, MONITOR SLOT and LIVE DECODERS show in both views.

• Color legend (advanced): green received, checked · amber needs your eye · light received, unverified · red sent by you · gray between frames.
• MONITOR SLOT — one button per slot (S1…), colored by live state. Pick a slot to watch its decoders.
• LIVE DECODERS — one card per decoder head on that slot, each showing its mode, center frequency, state, any provisional text mid-decode, and its figures — SNR 12 dB · peak 18 dB over noise. FSQ runs many decoders at once — that's how the whole channel is heard without you tuning anything. Click a card to filter the history to just that decoder.
• CHANNEL HISTORY — the durable log, with the columns Time, Addressing, Assurance, Message, Evidence and Operation. On FSQ the advanced filters separate Admitted, Review, Monitor and Rejected traffic; on AX1200 and JG25 they are the packet kinds — Messages, Actions, Control, Files and Rejected. Show unparsed packets controls whether raw fragments and wrong-speed copies clutter the view; hiding them does not erase them. Keep history controls retention and applies at once; Clear selected slot and Clear all erase the open slot or everything.
• Operation — protocol envelopes are summarized in human terms such as file DATA, block 5, object N or the corresponding AX packet operation. This is often the fastest way for an experienced operator to see what a “mystery frame” was doing.
• Decode Inspector — select any row for the verdict, admission checks, per-character confidence, decoder opinions, operation, and raw frame. Copy diagnostics copies the evidence for a bug report.
• Record diagnostics (advanced, on the row under the filters) — keeps a rolling ten-minute window of the receive audio exactly as the modem was given it, aligned with Channel history. Save bundle… writes a ZIP containing receive-audio.wav, the overlapping channel-history.jsonl, session-notes.jsonl, the receive-emphasis and JG25 reception logs, tx-path.jsonl with transmit-audio.wav, and session.txt — the configuration and version mapping. Turn this on before a hard-to-reproduce on-air test.

The Busy margin control on the Radio page's FSQ card belongs to this world: it's how many dB above a slot's own noise floor the signal must rise before the slot counts as busy (default 3.0 dB; 0 turns busy detection off). It gates only transmitting — decoding always runs.

Receptions that failed, on JG25

While Record diagnostics is on, a JG25 reception that never became a packet still gets a row. It is named JG25 receive rather than drawn as an arrow between two blank callsigns — nothing was recovered to read addresses from — and its inspector opens a Receive attempt group, followed by a Branches group, carrying the whole account: what the acquisition, header and body each decided, the mode and FEC if the header was read, the clock and timing figures if a body was demodulated, the SNR where the geometry allowed one, the busy-detector's capture with its RMS, peak, noise floor and why it closed, and the result of every equalization branch in the order they were tried. A field the decoder never reached reads null, never zero — a clock error of 0 ppm and a clock error nobody measured are not the same reading.

This matters because the alternative was silence: a reception that never acquired, one whose header checksum did not hold, and one whose header described an impossible frame all used to leave no trace at all, so a recording full of strong signals could sit beside a channel history with one row in it. Successful receptions keep their single traffic row — duplicating them would cost this page its readability for a comparison the diagnostic bundle supports better. The bundle now carries the same account as jg25-rx-attempts.jsonl and a jg25-summary.json whose funnel accounts for every reception, including the two losses that are not decode failures and look exactly like them: a reception the busy detector had no free slot for, and a good result the hand-off could not carry.

A successful frame can also be marked Rescued. On JG25 that means it decoded on a fallback equalization branch — the best-scoring branch could not produce it, which is the receiver telling you its emphasis setting is off from what this path wants. On AX1200 it means the frame check failed but OpenJSQ's own CRC-32 held, which points at a damaged end of transmission: an early unkey, a squelch tail, a discriminator transient.

15. The Radio page in depth ↑ contents

Everything hardware. Two habits to know: this page saves as you change things (no Save button), and the Show advanced settings toggle at the top right reveals the controls whose defaults already do the right thing. The pinned footer holds Start radio / Stop radio and a status line.

Radio & audio

• Audio input (from radio) / Audio output (to radio) — your interface's two halves. Refresh rescans after plugging something in. No output (receive only) makes a deliberately transmit-proof station.
• Sample rate (advanced, sound-card links only) — the rate the sound card is opened at, not the rate the decoders run at; OpenJSQ resamples between the two. 48000 Hz is the default and the right answer for almost every card. 16000 Hz (no conversion) is offered because it is the engine's own rate, so a device opened there skips the receive resampler entirely; 12000 Hz is kept only so stations that chose it years ago still find it. The list also offers 44100 Hz.
• Radio technology — FSQ, AX1200, and JG25 in a build that offers it — all three on one row, in the basic view as well as the advanced one. Switching while running asks first, then restarts cleanly. Each waveform brings its own settings panel below and hides the others'; section 16 compares the three and says which one you want. The buttons are disabled while you are actually transmitting.
• Receive effort — how hard to dig for weak signals, five steps from Maximum Reach (more marginal text, always marked unverified) through Reach, Balanced and Clean to Strict (fewer questionable receptions). Balanced is the calibrated default. JG25 does not use this setting: its Carrier-detect offset sets how readily it hears a packet.
• Receive emphasis — one control for how the incoming audio is corrected. Adaptive (recommended) lets wide FSQ modes learn a bounded correction for the radio's receive tilt from idle audio and freezes that choice during a signal; narrow classic FSQ is left untouched. Manual de-emphasis correction applies the fixed corrector to everything the modem hears, including AX1200, and reveals the De-emphasis corner — the frequency, 50–1000 Hz and 210 Hz by default, above which the correction begins to lift. 210 Hz matches the 750 µs shaping that land-mobile FM radios use, and it is not a number to agonize over: on the bench anything from about 150 to 450 Hz corrected the same radio equally well. Off passes sound-card audio through unchanged.

  What Adaptive learns is remembered against the audio path it was measured on — a particular sound device at a particular rate — not against the application. That matters: a correction learned through a de-emphasised FM rig would be actively harmful if it were reloaded into a session running on a flat virtual cable, so a path OpenJSQ does not recognise starts neutral and learns from scratch. If you suspect a remembered correction is doing harm, Forget learned receive emphasis clears every path back to flat; restart the radio afterwards so the filters rebuild cleanly.

• Channel mode (FSQ) — Multi — compatible (1500 Hz slot other FSQ programs use) (the default and the recommendation), Multi — dense (maximum slots, OpenJSQ only), or Single slot (classic FSQ at 1500 Hz). When your chosen mode is too wide to share, the box is greyed and says so — Single slot — FSQ-12 fills the channel — and the radio runs one slot automatically.
• Busy margin (FSQ) — how many dB above a slot's own noise floor a signal must rise before that slot counts as busy and holds your transmissions. 3.0 dB by default, 0.0–100.0 in tenths; 0 turns busy detection off. It gates only transmitting — decoding always runs — and changing it while the radio is running restarts the radio. Earlier builds kept this box in the top bar.

Transmit control (PTT) and level

• Keying, in the Transmit control (PTT) card: VOX — the radio keys on audio, Serial line — RTS/DTR (DigiRig, most interfaces) (pick the Serial port, and under advanced, the control line and polarity), or CAT — the rig control link keys the radio (for one-serial-port interfaces where rig-control software already owns the port). The page warns you about the classic conflicts, in red when it matters.
• Control line (advanced, serial keying) — which line on the port is pulled to key the radio: RTS (the default, and what a DigiRig and most interfaces use), DTR, or Both RTS and DTR for interfaces that will take either.
• Polarity (advanced, serial keying) — Normal (the default: the radio keys when the line goes high) or Inverted. The symptom that tells you to flip it is unmistakable: the transmitter keys the moment OpenJSQ opens the port and unkeys when you actually send.
• Key-up lead / Key-down tail (advanced) — milliseconds of key-before-audio and key-after-audio. 100 ms each suits most rigs; raise the lead for an amplifier. Choosing CAT keying raises the lead to 300 ms by itself, because a rig-control command takes longer to reach the radio than a serial line does.
• Transmit level — the Drive slider (attenuation from full scale), a peak meter, and Tune (FSQ only; greyed out on AX1200 and JG25). The procedure that matters: Tune into a dummy load, raise Drive until the rig shows your target power with little or no ALC, stop. A red Clipping warning means pull it back. If you see splatter complaints, this slider is almost always the answer.

Live status

The card that answers “is this station actually working?” without going on the air.

• Audio path — what the sound card is doing right now: Stopped, or Running at 48000 Hz followed by transmit and receive or receive only. It is the quickest way to confirm that the sample rate and the No output (receive only) choice took effect, rather than inferring it from silence. Two more states are worth recognising: after a refused start it reads Stopped. with the reason under it, and a stream that is open but delivering nothing turns red — No audio arriving from <device> — check the device, its cable, or Windows sound settings.
• PTT — the keying method, and under it idle, KEYED, transmit stopped by the operator, or UNAVAILABLE: with the reason. Unavailable means the station will decode all day and never transmit.
• Receive level — the same meter the wizard's Listen page shows. It should move with band noise and sit comfortably above its floor. When nothing at all is arriving it reads no audio instead of a dBFS figure, pinned at the bottom of its scale.
• Dropouts — audio the machine could not keep up with, counted separately for receive and transmit — receive: 0 samples, 0 events, transmit underruns: 0, and the device's own counts. All zeros, and the audio path is keeping up, is what a healthy station looks like. A number that climbs steadily means something is starving the sound card — another program competing for it, power saving, or a machine that is simply busy — and on the air it shows up as characters missing from the middle of otherwise strong receptions. Reset counters zeroes the tally so you can watch a change take effect rather than reading a total accumulated since you started.
• Stop transmitting — the same emergency stop as Stop TX in the top bar, within reach on the page where you set your levels. It drops the PTT line at once, throws away audio already queued at the sound card, and cancels everything still waiting to go out. It is enabled whenever the radio is running, so it is there before you need it.

Rig control (CAT) — advanced

Backend: None — OpenJSQ does not talk to the radio, flrig — already knows your radio, on localhost:12345, or Hamlib rigctld — more radios, better units, on :4532. With a backend connected you get live frequency/mode/meter readouts, a Set mode row to put the rig in its data mode, and the option of CAT keying. OpenJSQ deliberately shows — rather than a stale number whenever the link can't vouch for a reading.

• Address — host and port. The host is 127.0.0.1 and only changes if flrig or rigctld runs on another computer. The port box pre-fills from the backend you chose — 12345 for flrig, 4532 for rigctld — and follows a change of backend unless you have typed a port of your own.
• Read every — how often OpenJSQ asks the radio for its frequency, mode and meters. 1000 ms by default, 250–10000 ms. Polling faster is not free: both flrig and rigctld put every client behind a single lock, so anything else talking to your radio waits its turn behind you.
• While transmitting — by default OpenJSQ goes quiet on the CAT link for the length of a transmission (Stop reading while transmitting). FSQ's turnaround has no room to wait behind a routine S-meter read, so the readouts freeze rather than the transmission slipping. Keep reading is there for the rare setup that genuinely needs live meters under transmit, and it is worth choosing only if you know that is what you need.

Groups

Subscribed groups is a full-width card on the Radio page, because one group list serves every radio. Enter one per line or comma-separated; group names must begin with @ or #. The larger box is meant to be audited at a glance rather than treated as a hidden protocol setting.

AX1200 settings

• Radio link — four ways to reach the air, each with its own card of settings appearing underneath:
  • Built-in modem (sound card) — OpenJSQ generates the 1200-baud audio and keys your transmitter.
  • Bluetooth KISS TNC (its card below is titled Bluetooth KISS radio) — only for TNCs that expose KISS as a Bluetooth Low Energy service. Most handhelds are not this: a UV-PRO carries KISS over the Bluetooth serial port profile, so use Serial for those. (Grayed out if this build was compiled without Bluetooth support, and it says so.) Press Scan, pick the radio from the list — anything that advertised the KISS service is marked — KISS and sorted to the top — then Connect. A radio you have connected to before is remembered and offered without scanning.
  • Serial KISS TNC — BTECH UV-PRO and friends; the full pairing walkthrough is printed on the page. Port and Speed lock while the link is up.
  • Network KISS TNC — Dire Wolf and other software TNCs, over TCP. Host plus TCP port (8001 for Dire Wolf), Connect / Disconnect, and Reconnect automatically if the link drops (which is on by default here and on the Bluetooth and Serial cards too — all three have it). Host and port lock while connected — editing them under a live socket would be silently ignored. Status reads Not connected. → Connecting to … → Connected to …, with The connection timed out. and Reconnecting… when things go wrong.
• KISS port (advanced, in the KISS timing card on any KISS link, 0–15) — which radio port on the TNC your frames are for. Single-radio TNCs, and every handheld with one built in, use port 0 — leave it there unless the TNC documents otherwise. A multi-port TNC silently drops frames addressed to a port it has nothing on, so a wrong number here looks exactly like a dead radio.
• Allow the radio (advanced, in the KISS timing card on any KISS link) — how long a frame may still be sitting inside the TNC after the TNC has taken it: its own TX delay, its wait for a clear channel, and anything already queued ahead of it. OpenJSQ adds this to the frame's airtime before it decides an acknowledgment is late. 1500 ms by default, 0–30000 ms. Set it from the TX delay configured on the radio and round up generously — too long only delays a retransmission, while too short makes a perfectly good link re-send every frame before the first copy has finished going out.
• Network profile — Dedicated OpenJSQ channel or APRS coexistence (disables files, relay, and automatic signal reports; presence remains available).
• Files — Accept files from other stations, on by default, plus the advanced limits below. There is no separate AX receive-folder override now: every waveform uses the profile's common incoming folder.
• Announce now — an immediate AX1200 presence announcement. The automatic schedule and Presence status live in Settings → Presence and are shared with FSQ.
• Destination address (advanced) — the AX.25 destination call OpenJSQ puts on its own frames, APZJQ1 by default. It is how other software on a shared channel recognizes this traffic as OpenJSQ's rather than something addressed to a station. Leave it alone unless you are coordinating a channel where someone has asked you to use a different identifier.
• Digipeater path (advanced) — empty by default, and empty is right for almost everyone: OpenJSQ is normally worked simplex. If you do need to go through a digipeater, list the calls separated by commas, e.g. WIDE1-1, WIDE2-1. Every hop you add is another transmission of the same frame on the same channel.
• Chat format (advanced) — Automatic (recommended), and leave it there. On Automatic, simple live chat may go out in the older OFQ1 framing so that anything already on the channel can read it, while verified delivery, long messages, files, groups and station actions wait until the far end has been discovered to speak OFQ2. What they do not do is quietly downgrade: if the far end cannot do OFQ2, those actions fail and say so rather than going out in a form that cannot carry them. The two fixed settings, Full-featured format only and Compatible with older OpenJSQ versions, exist for testing a channel, not for daily use.
• Default chat delivery (advanced) — which of the two delivery kinds a new message starts with when you have not chosen one on the message itself. The shipped default is Live delivery, not Verified; section 10 explains the difference, and the chip on the compose row always overrides this.
• AX1200 relay (advanced, Forward other stations' AX1200 traffic onward) — whether your station forwards other people's AX1200 traffic onward, with a hop limit of 1–8, default 2. Off by default. See section 13 for what it then carries.
• Unasked signal reports (advanced) — whether your station sends a signal report, unasked, to each station whose AX1200 packets reach it, and at most how often per station: off by default, and no more than once every 30 s when on (5–3600 s). It does not decide whether you answer Ask for a signal report — that is Settings → Automatic replies, on every radio. This is not relaying and it is not presence; and it does nothing at all on a KISS TNC link, because the TNC receives for you and OpenJSQ has no measurement of its own to report.
• File size limits (advanced) — all incoming and all outgoing: separate ceilings for what you will accept and what you will send, 64 MB each by default (1–4096 MB). A transfer that would take you past a quota is refused rather than truncated, and the other station is told why.
• Files at once (advanced) — three numbers: receiving (16, range 1–128), from one station (4, range 1–32), and sending (16, range 1–128). The per-sender number is the one worth lowering if a single busy neighbour can monopolize your station; the others matter mostly on very small machines.
• File error correction (advanced) — how a file is armoured against loss: data blocks 16 (1–32) and repair blocks 4 (0–16). More repair blocks mean fewer round trips to fill in what was lost, at the cost of more airtime per block. The transport clamps at 32 and 16, which is why the controls offer no more.
• File transfer pacing (advanced) — three controls worth knowing by name: window (how many blocks may be in flight before the sender stops and asks what is missing), wait (how long it waits for that answer), and listen (how long a quiet channel must stay quiet before your station keys). Section 21 explains what to do with them when transfers misbehave.
• AX1200 changes made while running are applied at the next restart — leaving the page offers Restart now / Later.

16. Choosing a waveform: FSQ, AX1200 and JG25 ↑ contents

OpenJSQ is one program over three different radios' worth of physics. The waveform decides how fast you can talk, how bad the path may get before you stop being heard, and who else can decode you — but it does not decide what the program can do: chats, mail, files, groups, the network map and relaying are the same services on all three. Pick the one that matches the band you are on, and change your mind later on the Radio page.

The three at a glance

Which one do you want?

• You are on HF. FSQ, and nothing else in this table is a candidate. It is the only one of the three designed for a band where the signal fades, the path is long and the noise is the limit — it stays readable well below the level at which you could hear a voice, and the four classic speeds reach every fldigi and FSQCall station on frequency. Start at FSQ-3.
• You are on 2 m or 70 cm and want to reach other people's equipment. AX1200. It is the classic VHF/UHF packet layer, so a TNC, a Mobilinkd, Dire Wolf or another operator's packet station can all copy you, and OpenJSQ can either be the modem itself or hand the job to a TNC you already own.
• You are on FM and everyone you are talking to runs OpenJSQ. JG25 — if your build offers it. It is roughly twice AX1200's raw rate at the top of its range, it carries forward error correction AX1200 has no place for, and it needs nothing but a sound card. What you give up is everybody else: no other program decodes it.
• You are not sure. AX1200 on VHF/UHF, FSQ on HF. Both are finished work; JG25 is not, and being unsure is a good reason to be on the interoperable one.

JG25 in the program

JG25 is OpenJSQ's own packet waveform: continuous-phase 4-FSK carrying two bits per symbol, a slow protected header in front of every frame that names the speed and coding used, convolutional forward error correction over the body, and a CRC-32C the receiver checks before it will accept anything. It carries the whole service stack natively — chat with fragmentation, verified chat, reliable files with whole-file verification, custody mail, station actions, one-hop relay and delivery receipts.

It appears only in a build compiled to offer it. In a build without it, JG25 is reserved and unselectable, and the program says so rather than offering a waveform it cannot start; you will not see a JG25 button on the Radio page or a JG25 entry in the first-run wizard.

Mode

Seven modes, JG25-FM 1200 to JG25-FM 2400, named for their raw bit rate. This sets what you transmit, and only that — the frame header tells the receiver which mode was used, so the far station follows you automatically and the two of you do not have to agree in advance.

Faster modes pack more into the same bandwidth and survive less. On a weak or fluttery path a slower mode gets through where a faster one does not decode at all. JG25-FM 2400 is the narrowest margin of the set, and it is the default because it is the mode JG25 was validated at; if it struggles on a path, Robust acquisition is the first thing to try.

Error correction

Spare bits sent alongside your data so the receiver can rebuild what the noise damaged without asking you to send it again. The rate is how much of the frame is your data:

Like speed, this is a choice about what you send: both stations choose independently and the header carries the answer. There is no automatic ladder yet — the pairing that suits the path is the operator's call, which is exactly why both controls are on the top bar as well as on the Radio page.

The rest of the panel

• Acquisition — how long a preamble goes out in front of each transmission. Normal is the everyday setting; Robust roughly doubles it, which helps a receiver find a weak or fading signal at the cost of a slightly longer transmission. Both stations choose independently: the receiver detects which preamble it heard, so you can work a station set the other way.
• Adaptive receive equalization — on by default. Real FM audio is not flat, and the tilt differs from radio to radio; this measures it and corrects for it. Turn it off only to compare against a known-flat path.
• Carrier-detect offset (advanced; a different setting from FSQ's Busy margin, which JG25 does not use) — how far above the noise a signal has to be before JG25 calls the channel busy and holds your transmission. 0 dB is the calibrated default. Raise it if a noisy receiver keeps your station off the air; lower it if you find yourself transmitting over other people.
• Transmit turnaround (advanced) — quiet time between this station's own transmissions, measured from the moment PTT drops to the moment it may be asked to key again. It is there for the radio: the T/R relay, the PA and ALC settling, and the far receiver's AGC recovering. 1.5 s by default, adjustable from 0 to 30 s.
  Why this control exists
  On the bench a queue that keyed again 10–40 ms after unkey lost about four packets in ten, in both directions. Replaying the recorded audio offline loses exactly the same packets — so the damage is in the transmitted waveform, before any decoder sees it, and no amount of receive-side work recovers it. 1.5 s is a deliberately conservative starting point, not a measurement: lower it once an on-air sweep tells you what your pair of radios actually needs.
• Announce now — an immediate presence announcement. The schedule and the status text live in Settings → Presence, one setting for every waveform.

17. The FSQ mode ladder ↑ contents

This section is about FSQ. AX1200 has one speed and JG25 has its own seven — section 16 covers those. The top bar's Mode box lists eleven FSQ modes. The first four are classic FSQ — every FSQ program ever shipped decodes them. The seven below the separator are OpenJSQ-only Fast modes: the same waveform run faster and wider. Changing mode restarts the radio (a transmission in progress finishes first).

Every step up the ladder costs sensitivity, and predictably so: about 3 dB for each doubling of speed, 8.5 dB from the bottom rung to the top. The mode list's tooltips carry each mode's requirements. Beyond that physics, two rules keep the Fast modes civilized, and the app enforces both:

• Capability is negotiated. Stations advertise what they decode inside the standard version reply. A classic fldigi station is never sent a mode it can't copy.
• Wide modes wait their turn. From FSQ-12 up, your signal occupies most of the channel, so OpenJSQ holds the transmission until every slot is quiet — for up to the time set in Settings → Channel courtesy (default 30 seconds).

18. Settings in depth ↑ contents

Unlike the Radio page, Settings stages your edits: nothing takes effect until Save & restart radio (theme and text size are the exceptions — instant). Show advanced settings reveals the extra cards. The cards run Station, Known callsigns, Automatic replies, Mail, Shared files, Presence, Channel courtesy, Receive coverage, Appearance, Alerts, Files & configuration and About; while FSQ is not the selected radio, the settings that apply only to FSQ are hidden and the page says so.

Station

Callsign — the base call alone. A packet SSID such as -7 is not part of it: type one here and a note says so and Save is refused; pick the SSID on the Radio page instead. A callsign already saved with an SSID is kept, with a note asking you to remove it. Location (sent when asked), Station message (sent when asked). Advanced, and shown only while FSQ is selected: Check every message for corruption — adds a 5-character checksum to each message; off by default on the classic modes because fldigi shows those characters as line noise, always on in OpenJSQ-only modes.

Mail

Accept stored messages (mailbox), and Hold letters for other stations (the community-mailbox switch, on by default). Advanced: Give up on undelivered letters after (12 hours … 30 days, default 7 days — a ceiling, so a letter that arrived with a shorter deadline of its own keeps it) and Tell a station it has mail at most (every 30 s … 15 min, default 2 minutes). The second is not how often mail is delivered — a station that answers gets its letter at once; it is how often the “I am holding mail for you” notice may repeat, which is airtime everyone on the channel pays for.

Shared files

The switch is not here. Sharing on/off, the folder, who may browse, the allow-list and serve-automatically all live on the Files page — one home for the whole file service, so no control exists in two places and can be set two ways. What this card carries is a read-only summary in the same words the Files page uses (“File sharing: On · 6 files offered · folder …”), a Manage in Files button that takes you there, and, under Show advanced settings, the five technical limits: Include subfolders (No), Largest file to serve (256 KB), Serve at most, per day (Unlimited), Each station may ask every (10 s) and Approval timeout (2 minutes). Section 11 covers all of it, including which of those limits protects the whole channel rather than just you.

Presence

One schedule for every waveform: Announce my presence plus Presence status. AX1200 carries the status in its beacon, JG25 in its presence announcement, and FSQ sends it as a status-bearing automatic Allcall line. Clear the status to get the classic bare FSQ sounding. The interval list also carries an Every minute entry marked (bench) — it is there for testing on a cable and is far too often for a shared channel.

Two advanced fields decide how long a station you have heard goes on counting, and they are not the same thing:

• Stations drop off Nearby after — 2 hours by default (10 minutes to 8 hours, or Never). This only stops a station counting as on the channel now; the row stays where you can see it.
• Forget stations not heard for — 24 hours by default (1 hour to 7 days, or Never forget). This one actually removes the station: it leaves Nearby, the station list, and the suggestions you get when addressing a message or a letter. New hearings are judged by the new age at the next radio start.

Alerts

Sound when a message arrives (On/Off), and — important — Play alert sounds through. Point this at your speakers, never the radio's sound card: OpenJSQ detects that conflict and silences alerts rather than transmitting your chime, but naming the right device is better. Test sound checks it. The list starts with two entries that are not devices: System default output, and Silent (no sound) — the way to keep the arrival chime switched on while producing no sound at all, which is what you want on a machine sharing a room with the radio.

The rest, in one table

19. Profiles: one program, many stations ↑ contents

A profile is one theater of operations — the shack, a POTA kit, an ARES deployment. Each one keeps its own callsign and radio setup, its own conversations, mail, network map, and files, and nothing crosses between them. If you operate in more than one situation, this is the feature that stops the situations contaminating each other.

What a profile owns, and what it doesn't

Working with profiles

• The profile button in the top bar — it shows the active profile's name — switches between them; each entry reads Home — N0CALL. The radio has to be stopped first — OpenJSQ will offer to stop it, and if it cannot, it changes nothing and tells you so rather than half-switching.
• Manage profiles… opens Listening profiles, which creates, switches, renames, duplicates, and deletes; the profile you are using, and the last one left, cannot be deleted. When it asks you to name this profile — where or what it is for, take the prompt literally: Shack, Truck, Field Day beat Profile 2 at three in the morning.
• Duplicating copies the radio setup, the conversations and the channel history, and gives the copy an empty files folder. Mail, held letters and file history stay with the original. It is the quick way to build a portable profile from a working shack one without setting up audio twice.
• Deleting takes the settings, conversations, mail, and channel history with it, and cannot be undone — the dialog shows you exactly which folder is about to go. Files you served over the air are left alone; they live in your documents, not inside the profile.

Two things people get wrong

A profile is a folder

Everything a profile owns lives in one directory, which makes the whole station portable: copy it to the field laptop and you have the same setup, the same mail, and the same history. Settings → Files & configuration (under Show advanced settings) names it: the Settings file row prints the profile's openfsq.ini, and the Open folder button beside it opens the profile directory. It also makes backup obvious — copy the folder before a deployment, and a mistake in the field costs you nothing at home.

20. Where your files live on disk ↑ contents

21. Troubleshooting ↑ contents

22. Glossary ↑ contents

23. Numbers and defaults at a glance ↑ contents

Every default and limit the rest of this document mentions, in one place. None of these is something you have to set. They are the answers OpenJSQ already gives. Useful when someone asks "what is yours set to?", and useful for deciding what to change first.

On the air

Receive

Mail

Files

Numbers other people's software cares about

OpenJSQ by Jerome Goddard II (W4IJG) · Copyright © 2026, All Rights Reserved · current OpenJSQ source is distributed under the repository's proprietary license; third-party material keeps its own license terms. FSQ was designed by Murray Greenman ZL1BPU and Con Wassilieff ZL2AFP.
Describes OpenJSQ 1.0 as shipped, September 2026 — what the program does today, not what is planned. Labels quoted in blue match the program's own text. Build reference: the text was checked against commit b0c8b01a on main, 15 September 2026, and the Help button that opens this guide, and the JG25 button in the Radio page's basic view, arrived in the build of 16 September. The screenshots were taken the same day from that commit, compiled with the experimental JG25 provider enabled so its controls could be photographed, on a bench of two stations (N1TSA and N1TSB) joined by a virtual audio cable; where a picture and the text disagree, the text is current.