Toggle MOX to manually key the transmitter¶
MOX lets you key the transmitter without a footswitch or PTT line. Use it to check audio, test your signal, or transmit when hardware PTT is unavailable.
Before you start¶
- AetherSDR must be connected to the radio. MOX has no effect when the radio is offline.
- Confirm your TX profile and RF Power level are set correctly before keying.
- In v0.9.7, if you have Quindar tones enabled in the Audio Channel Strip, the K and BK tones will play automatically when you engage and disengage MOX on phone modes. No additional configuration is required.
Steps¶
- If the TX Controls applet is not visible, click the TX tray button on the right sidebar to show it.
- Locate the MOX button in the button row alongside TUNE, ATU, and MEM.
- Click MOX to key the transmitter. The button turns red while TX is active.
- Click MOX again to unkey the transmitter. The button returns to its unlit state.
What each control does¶
| Control | Behavior | Default |
|---|---|---|
| MOX | Toggles manual transmit on or off. Button goes red while the transmitter is keyed. In v0.9.7, the click routes through the Quindar-tone coordinator so K/BK tones play on engage/disengage in phone modes when Quindar is enabled in the Audio Channel Strip. | Off |
| RF Power | Sets the transmit RF power level sent to the radio. | 100 |
| RF Pwr meter | Displays forward power at the exciter output. Turns red above 100 W (barefoot) or 500 W (Aurora 500W). | — |
| SWR meter | Displays standing wave ratio at the exciter. Turns red above 2.5. | — |
ATU button behavior¶
Starting in v0.9.5.1, the ATU button toggles between starting a tune cycle and bypassing the tuner, matching the per-frequency behavior of SmartSDR.
The button follows this logic each time you click it:
- First click on a new frequency — starts an ATU tune cycle.
- Second click at the same frequency, after a successful tune — switches the ATU to bypass.
- Any click after a frequency change — starts a fresh tune cycle, even if the previous tune was successful.
Entering bypass clears the remembered tuned frequency, so the next click always starts a fresh tune cycle.
The ATU and MEM buttons are disabled when TGXL is in OPERATE mode.
Tips¶
- Watch the RF Pwr and SWR meters as soon as you key MOX. If SWR exceeds 2.5 (red zone), unkey immediately and investigate your antenna system.
- Set RF Power to a low value before using MOX for the first time on a new band.
- MOX keys the radio into full-power transmit in whatever mode is active. If you only need to check SWR or tune an ATU, use TUNE instead — it transmits a carrier at the lower Tune Pwr level.
- After a successful ATU tune, clicking ATU again on the same frequency puts the tuner into bypass. To re-tune after changing bands or frequencies, simply click ATU once on the new frequency.
- If Quindar tones are enabled in the Audio Channel Strip, switching to a digital or CW mode suppresses the K/BK tones automatically. MOX itself behaves the same regardless of mode.
Troubleshooting¶
- MOX button is unresponsive — Confirm AetherSDR is connected to the radio. The TX Controls applet requires an active radio connection.
- Transmitter keys but no RF power is shown — Check that RF Power is not set to 0 and that the correct TX profile is loaded in the TX Profile selector.
- Radio stays in transmit after clicking MOX a second time — Another PTT source (footswitch, VOX, CAT command) may be holding the radio keyed. Check external PTT hardware and any connected CAT clients.
- ATU button starts a new tune instead of bypassing — The transmit frequency has changed since the last successful tune. The ATU button will always start a fresh tune cycle when the frequency differs from the frequency at which the tuner last reported a successful match.
- Quindar tones do not play when clicking MOX — Confirm that the QUIN chip is enabled in the Audio Channel Strip and that the active TX slice is on a phone mode (SSB, AM, FM). Quindar tones are not generated on CW or digital modes.