Quick‐Start Guide for Android Panadapter for QMX Series Transceivers
Quick-Start Guide for Android Panadapter for QMX Series Transceivers
Version: 1.1 Date last modified: 30 April 2026.
Compiled by Scott Schillereff VA7SNJ; reviewed by Vojtěch Bubník OK1IAK and Peter Dittus HB9EBE.
Purpose
This guide provides basic instructions for configuring an Andoid device (e.g., cell phone or tablet) as a panadaptor (panoramic adapter) to graphically display signals and waterfall record over a chosen frequency spectrum (typically part of an amateur radio band).
The main value of this is to utilize a common cell phone to show a ham band waterfall and provide a speaker for your QMX/QMX+ transceiver (see image below; from QRP Labs GroupsIO post #167889, from Ivars Ivansons, 13 April 2026).
This guide is not intended to provide suggestions for advanced settings but, rather, the basic steps to get you started. It will be stored here: https://github.com/bubnikv/SDRPlusPlus-iak/wiki and will be occasionally updated.
Hardware Needed
- Any Android device (new or old). Android versions: For android 7.1 and older, you will need to enable developer mode and then disable USB audio routing in developer menu to hear audio from your phone.
- USB-C (male) to USB-C (male) data cable. Must use data cable, not just any charging cable. (Optional: it helps to have one end at right-angle to snug into side of QMX case). If you are using an older android device with a USB micro-b connector, you must use an OTG adapter cable to force the phone/tablet into USB host mode, otherwise it will not connect to QMX.
- QRP Labs QMX (any band configuration) or QMX+ transceiver.
Firmware/Software Needed
- Update your QMX with latest firmware (see QMX Operating Manual for steps to do this).
- The app automatically sets QMX into I/Q mode; there is no need to manually set it.
- Download the SDR panadapter app onto your Android device from here:
Follow the prompts during download. This icon appear should appear on your device:
All SDR++ iak app (IAK app) releases are stored here:
https://github.com/bubnikv/SDRPlusPlus-iak/releases
You can simply download the latest and greatest.
Connecting your Android Device to QMX
- Turn Android device on, connect USB data cable between device and QMX USB ports, and tap the IAK icon on device to start the app.
- Turn QMX on. On Android device, give the IAK app the requested permission when the pop-up window appears.
- Within the IAK app, open menu (tap three-line "burger" symbol in upper left corner).
Under Source, select QMX (from drop-down menu); tap Sync VFO to ON. The Device line should show QMX USB (in green; means you are connected!). If it shows Not connected (in white), this means your USB cable is not a data cable, or has a bad connection.
Layout of IAK App Screen
The image below shows screen elements of the IAK app when active, with menu open.
Legend:
- Menu icon – tap to open/close menu. Note: to change width of menu, touch and drag vertical boundary line (highlighted as vertical yellow line) left or right.
- Menu row – tap symbol to expand/shrink submenu rows
- Menu row slider - touch and drag to show rows
- Play/Stop button – tap square to start play; tap triangle to pause/stop.
- Speaker on/off – tap to toggle IAK app audio on/off.
- Volume control – drag to right for louder audio from Android device. Note: QMX and IAK app audio circuits are completely separate. For example, where you want to listen silently, you could toggle the IAK audio off and listen to QMX with earbuds.
- Frequency – example shows 21.074090 MHz
- Linkage icon to QMX - double arrow symbol means frequency of IAK app and QMX will exactly track together. The other symbol (bulls-eye) is not used at present in IAK app.
- Signal strength indicator – varies with strength of incoming signal; not calibrated as S units at present.
- SDR identification icon – lists authors/contributors to SDR platform, for information.
- Frequency zoom slider – changes frequency range of spectrum displayed (see 16).
- Max dB slider – slide to adjust upper bound of spectrum dB range (see 19).
- Min dB slider – slide to adjust lower bound of spectrum dB (see 19). Easiest to move Min as high as possible (to give -150 dB lower bound), then adjust Max to about -120 dB to shows active signals. Play with max/min settings for desired amplitude of spectrum and “blueness” of the waterfall. Optional: can remove active signal traces by setting min to -120 dB; no “dancing traces” will be shown.
- Ham band spectrum range – colour band shows name and extent of ham bands. Can be set to display at top or bottom of spectrum range (Menu> Band Plan> Position).
- Spectrum signal traces – active signal traces for incoming signals.
- Frequency range bar – shows frequency range selected. Adjustable by Zoom slider (11) and QMX frequency knob.
- Waterfall – shows trailing record of received signals (this example during solar storm, so no signals showing; just cosmic hash). Useful to quickly find signals on a band. Note: balance of screen space between the upper spectrum and lower waterfall can be adjusted by touching and dragging horizontal boundary line (highlighted as yellow horizontal line) up or down.
- Frequency indicator line – red line showing current active frequency. Can move by touching area of interest on spectrum (red line will jump there). Can also touch and drag the frequency range bar (16) left or right to shift entire spectrum.
- dB range of signals – adjust to -100 to -150 dB using max/min sliders to show traces.
For the many other settings possible, please see the SDR++ manual at: https://www.sdrpp.org/manual.pdf.