Quick Start¶

Get your QMX Panadapter on air in 10 minutes.

Prerequisites¶

M5Stack Tab5 (ESP32-P4, 5" display)
QRP Labs QMX or QMX+ transceiver
USB-C power cable (5 V / 2 A minimum)
USB-A to USB-C data cable (connects Tab5 to QMX)
WiFi network (optional, for remote control and logging)

Step 1: Verify QMX Firmware¶

Power the QMX on standalone and check the firmware version displayed on its screen. You need v1.03.002 or newer. If yours is older, update the QMX first — everything that follows depends on recent firmware. Everything from v1.03.002 up to and including v1.04.010 works with the panadapter; on v1.04 you additionally get AM mode and an Antenna Tune button (SWR tune with a live power/SWR readout). Both stay hidden on v1.03.002, so either firmware is fine.

!!! warning "Stay on v1.04.010 for now"

**v1.04.011** (19-Sep-2026) is not recommended with the panadapter yet. One operator reports the radio producing **no transmit output** when keyed over CAT from the Tab5, and others report the radio's own Tune SWR and Hardware Test screens freezing until it is power-cycled — all of which go away on v1.04.010. These are being reported to QRP Labs. If you are already on v1.04.011 and see either, roll back to v1.04.010.

Step 2: Flash the Tab5¶

Download the latest flasher from the Releases page:

WindowsmacOSLinux

Plug Tab5 into your computer with a USB-C data cable
Double-click flash.bat
Press Enter for a normal flash (keeps your settings) or type E for a clean flash (wipes everything)
Wait for SUCCESS

Plug Tab5 into your computer with a USB-C data cable
Open Terminal and run: bash flash.command
If you haven't installed esptool: brew install esptool
Press Enter for normal flash
Wait for SUCCESS

Plug Tab5 into your computer with a USB-C data cable
Run: bash flash.command
If you haven't installed esptool: pip3 install esptool
Press Enter for normal flash
Wait for SUCCESS

The firmware is already inside the zip — the three .bin files next to the script are what get flashed. The only thing fetched from the internet is esptool, once, if your computer doesn't already have it, so after the first successful run the flasher works offline.

Step 3: Connect the Cables¶

You need two USB connections:

Connection	Tab5 Port	Cable	Carries
Tab5 <- QMX	USB-A (host)	USB-A to USB-C, data cable	I/Q audio + CAT control
Tab5 <- Power	USB-C	Any USB-C power cable	5V power

⚠️ Cable gotcha: Many USB-C cables are charge-only. If the spectrum stays flat and the top bar shows Band: ---, you have a charge-only cable. Swap it for one you know does data (USB stick, phone sync, etc.).

Step 4: Power On¶

Tab5 first — turn it on. The screen fades up gently from black as it loads.
Wait for the Tab5 to settle before switching the radio on. Give it until the spectrum is running and the WiFi indicator in the bottom bar shows a network — usually a few seconds after the screen appears.
QMX last — now turn on the QMX. Until the radio is connected, the Tab5 shows a full-screen "turn on / reboot your QMX" prompt — that's normal, not a fault, and it clears automatically once the QMX is talking.
Within a few seconds the top bar should show Band / Mode / BW, and the spectrum should come alive

!!! warning "Don't switch the QMX on while the Tab5 is still starting up"

It is tempting to power everything from one switch, or to turn the radio on straight
after the Tab5 so it is ready sooner. Avoid it for now.

The Tab5 sets up WiFi, the web server and the decoders in its first few seconds, and a
radio appearing over USB in the middle of that competes for the same small pool of
internal memory. The result is a Tab5 that comes up short of memory for the rest of the
session — the web interface may be unreachable, and it makes a crash more likely.

Waiting a few seconds avoids it completely. This is a limitation of the current
firmware rather than something you are doing wrong, and it is on the list to fix.

Step 5: Fill in Your Settings¶

On first boot you'll be prompted for:

Callsign — your amateur radio callsign
Grid — your Maidenhead grid square (e.g., JO45)
WiFi — SSID and password (optional, skip if you're portable)

You can change these anytime by swiping right from the screen edge to open the settings drawer.

Step 5b: Optional — microSD Card (station backup)¶

Insert a microSD card (a plain FAT32 32 GB card is ideal) into the Tab5's slot and it automatically mirrors your whole station to /qmx-panadapter/ on the card — a grab-and-go backup you can pull into a PC or another Tab5, no computer needed in the field:

ADIF QSO log — mirrored after each new QSO
Config export — all settings + memory channels (restore via the web Config upload)
LoTW certificate + key — so a restored device can sign QSOs for LoTW
Diagnostic log — rolling copy
README.txt — describes every file on the card

The SD dot in the bottom status bar shows what is happening:

Green — writes are reaching the card (something landed in the last 90 seconds).
Yellow — a card is mounted, but nothing has been written lately. On a quiet session that can simply mean there was nothing to write; if it stays yellow while the Tab5 is busy, writes are failing — see Troubleshooting.
Grey, struck through — no card in the slot. Not an error.

With WiFi off (normal POTA/SOTA operating) everything is mirrored continuously. With WiFi on the card and the WiFi co-processor share a bus and can't both use it reliably, so the Tab5 takes the full backup within a few seconds of switching on and then only keeps the diagnostic log and CW transcript going every 30 seconds. QSOs made later in that session are written at the next start-up.

After inserting the SD card your Tab5 needs a restart. The card is claimed during a short window early in boot, so one pushed in while the Tab5 is running isn't used until you restart it.

⚠️ The backup contains credentials (WiFi password, QRZ/eQSL logins, LoTW private key) — keep the card physically secure. Skipping this step is fine; your logs and settings always live in the device's own storage too.

Step 6: Navigate the Screen¶

The entire app runs on edge swipes and taps on the top bar:

Action	Does
Swipe → from left edge	Cycle Panadapter -> FT8/FT4/JS8 -> WSPR
Swipe ← from right edge	Open settings drawer
Swipe ↑ from bottom edge	Open memory channel picker
Tap any top bar item	Open that item's selector (Freq, Mode, BW, etc.)

You'll see faint "breathing" grip handles on the edges — they show you where to swipe.

Step 7: Start Listening¶

You're now receiving. The spectrum shows signal strength across the band, and the waterfall scrolls down showing signal activity over time.

Tap the spectrum or waterfall to tune to that frequency
Pinch to zoom in/out; one-finger horizontal drag to pan and retune
Tap the coloured band-plan strip (along the bottom, just above the status bar) to jump to a frequency, or drag along it to scrub through the band — you can also grab it from anywhere on the bottom bar and drag sideways (a vertical up-swipe there still opens memory channels)
Tap the Freq label on the top bar to open the frequency keypad — drag the "Enter freq" title bar to reposition it, pinch or swipe up/down to resize it
Swipe ↑ from the bottom edge to open memory channels — tap an empty slot to create one, long-press a filled slot to edit it, long-press and drag to move a channel (or drag it onto the wastebin cell to delete it). A new device comes with a few example channels and plays a one-time tour of these gestures the first time you open the picker
Tap Band to switch between your configured bands
Tap Mode to switch USB/LSB/CW/DiGi

Step 8: FT8, FT4 and JS8 (Optional)¶

Swipe → from the left edge to switch to the decode view. You'll see:

Live decode list — every station heard on frequency
Waterfall — same real-time spectrum waterfall
Call CQ button — transmit a CQ (requires QMX to be on the air)
Reply rows — tap a station to reply to their CQ

Three modes share this page. Tap the Preset button at the top of the left column to pick FT8, FT4 or JS8; the Tab5 retunes to that mode's calling frequency on the band you are on.

JS8 (beta) is the keyboard mode: it carries free text instead of FT8's fixed exchange, so you hold a short conversation. In JS8 the page gains a Conversation tab beside Stations, and a Free text button under Call CQ opens a box to type a message — it tells you how many seconds the message will hold the frequency before anything is transmitted. See JS8.

Step 9: WiFi & Web UI (Optional)¶

If you set up WiFi:

Open your browser to http://qmx.local (or the IP shown in the Tab5's bottom bar, if your network blocks .local names)
You'll see a remote spectrum, waterfall, and control panel — plus QSO log downloads and uploads to QRZ, eQSL, and LoTW
No installation or configuration needed — just open and go

Step 10: Keeping It Up To Date¶

From v1.8.9 the Tab5 can update itself over WiFi. You do not need the cable again unless something goes badly wrong. The version on the bottom bar turns amber when a newer one exists; tap it, choose Download now, and then Restart now when it suits you — nothing is fetched or installed until you ask for it.

!!! warning "v1.15.0 needs a USB-C cable, once"

v1.15.0 reclaims 2.81 MB of flash that had never been used, and that means
rewriting the partition table — something an over-the-air update cannot do,
by design. It is the only release that needs the cable, and afterwards
over-the-air updates work as before, with more than twice the room.

So v1.15.0 comes as a **flasher download**: the same USB-C data cable and
the same script you used to install the firmware the first time.

If you tap the update notice instead, it will simply fail — there is no
over-the-air image to fetch, on purpose.

**Your settings, memories, QSO log and LoTW certificate are kept.** Press
**Enter** at the flash-type prompt — not **E**, which erases everything
including your LoTW private key.

You will not have to remember this. When that release appears, the update
window tells you instead of offering a download.

When a newer release is available, the version at the bottom of the screen changes to show it, in light green, and breathes gently so you notice it:

v1.14.3 -> v1.14.4 ?

Tap the bar — anywhere along it — and a window opens in the middle of the screen with the version and two buttons:

Download now — the download runs in the background while the spectrum, waterfall and FT8 decoding keep working. Expect a slight stutter and one brief pause right at the end while the new firmware is verified.
Dismiss — the window closes. The line stays, quietly, and tapping it opens the window again whenever you are ready.

While the download runs the window shows the percentage:

Downloading  42%

When it finishes, the same window offers Restart now — the screen goes dark and the Tab5 comes back on the new firmware, about 20 seconds.

Nothing is fetched until you press Download now, and nothing restarts until you press Restart now. It can never interrupt a contact.

The same window is available from the web page, in the same words.

Checking straight away¶

The Tab5 looks for a new release every 30 minutes, so an announcement can take that long to show up. If you have just read that a release is out and want to see it now, tap the version even while it says you are up to date. The window offers Check now. Tapping the version in the web page does the same.

That is also the quickest way to satisfy yourself the whole mechanism works before you ever need it.

Your settings, QSO log, LoTW certificate and memories are untouched by an update. The previous firmware is also kept, so a failed update falls back to it by itself.

⚠ Restarting the Tab5 with the QMX connected usually means switching the radio off and on again afterwards — the screen will tell you if so.

Troubleshooting¶

Spectrum is flat? - Check the USB cable between Tab5 and QMX — charge-only cables won't work - Verify QMX is powered on and not in standby - Restart both devices (Tab5 first, then QMX)

QMX doesn't appear? - Check QMX firmware version (Step 1 above) — v1.03.002 up to v1.04.010 (not v1.04.011 yet — see Step 1) - Try a different USB cable

Flashing keeps failing, but the COM port is there? - Reboot the Tab5 and try again — do this first. The Tab5's USB serial connection is produced by the ESP32-P4 itself rather than by a separate chip, so a busy running firmware can leave the port listed in Windows Device Manager while it no longer answers the flasher. A reboot clears it. - Then the usual suspects: a charge-only USB-C cable, or a serial monitor still holding the port.

WiFi won't connect? - Check your SSID and password spelling - Restart the Tab5 and try again - See Troubleshooting for more

Still stuck? - Ask the Tab5 first. Open the settings drawer (swipe in from the right edge) and tap Need guidance? — pick the symptom in plain words and it opens the manual at the answer. Anything the device can see for itself is highlighted at the top of that list. See Getting Help - The diagnostic log is always on — nothing to enable. Download it via the web UI: open the Files menu in the web page's bottom bar and click Diagnostic download ↓ (downloads both the live log and the saved pre-reboot copy), or pull qmx-log.txt from an inserted microSD card - Report the issue on GitHub Issues or the QRPLabs Groups.io thread and attach the log

Next steps: Read the full User Guide, or dive into FT8 Transmit or JS8.