⚙️ 1. Verify KX3 Mode and Submode
Digital modes on the KX3 depend on the correct mode and data submode. Tap MODE until DATA A (or DATA AFSK) appears on the display. DATA A uses the MIC/ACC input for audio. DATA B uses the USB input (if configured) — not used for soundcards. Hold DATA (or access Menu → DATA MD) and confirm: DATA MD is set to AFSK A (not PSK D, which disables the external audio input). If it’s on PSK D or RTTY D, the radio expects internal text encoding, and you’ll see no RF output when sending tones from the PC. This is the most common cause of “triggers PTT but no RF output.” 🧩 2. Check Audio Input Selection Open the KX3 menu → MIC SEL and set it to ACC (or MIC+ACC if needed). This ensures that the rear-panel ACC1 (soundcard) input is used for transmit audio. If it’s set to MIC only, the external soundcard tones are ignored. Confirm MIC GAIN (front panel or menu) isn’t zero — set it around 20–30 for testing. 🔊 3. Observe ALC and Power Indicators With a carrier transmitting from WSJT-X or similar: Watch the ALC bargraph and power output on the KX3. If no ALC movement → audio isn’t reaching the modulator. If ALC moves but no RF output → incorrect submode (see Step 1). 💻 4. Confirm Soundcard Levels Since your K3 works fine with the same setup, the soundcard and software are good, but: Check that Windows didn’t reassign or mute the ROCCAT output when you reconnected the KX3. Set playback volume around 50–70%; if it’s too low, the KX3 won’t see sufficient audio input. 🔌 5. ACC1 Connection Make sure you’re using the tip and ring correctly on the 3.5 mm plug: Tip = audio from PC to KX3 (TX audio) Ring = audio from KX3 to PC (RX audio) Sleeve = ground If this cable is damaged or a mono plug is used, transmit audio won’t get through even though CAT/PTT works. 73 -- Matt N3AR > On Nov 4, 2025, at 4:16 PM, Jim Ruff via Elecraft <[email protected]> > wrote: > > I hadn't used my KX3 in over 6 mo. When I hooked it up, it operated perfect > in SSB and CW. When I went to TX in digital modes like FT-8 or PSK-31, it > would trigger the rig but there was no power out. My setup is: KX3, KPA100, > Dell computer, Windows 10 and a ROCCAT soundcard. . This setup has always > worked as it should in the past.Here is what I have tested: > - I tested with my K3 using the same setup as the KX3 and it operated > perfectly. > - I switched computers while using the KX3 and had the same problem. > - The issue persisted regardless of whether I was using the KPA100 or not.. > - I used the calibration tool in the utility and it tested successful. > - I've adjusted the soundcard volume which always worked to adjust the ALC > and it had no effect. > I'm thinking the issue is with the KX3 but have no idea where. Any thoughts > on how to fix? My frustration level is through the roof. > Thanks,Jim W7JHR > > > > > > > > > > > > > > Sent from Yahoo Mail. Get the app > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:[email protected] > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > Message delivered to [email protected] ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [email protected]
