Hi all. Yesterday afternoon my K3 #2887 was merrily transmitting 33% at 5W on 17m for WSPRnet as normal when by chance I noticed the external wattmeter was showing no power out on transmit - none at all, not a squeak. The internal wattmeter is also showing no power out, aside from the first bar permanently lit in TX. The receivers still seem to be working fine.
The rig was working OK up to then and has been since mid-April. I wasn't fiddling with any of the settings at the point it packed up, but before anyone asks here are the ten checks I've done so far: 1. I tried sending CW and SSB - neither works. Nor does TUNE, at any power setting. Nor does any other band. 2. I tried using VOX on both semi and full break-in, and PTT - no joy there either. The TX LED lights as expected but no watts escape. 3. I've plugged a 100W dummy load directly into the ANT2 socket, selected ANT2 and tried transmitting, just in case there's some cable or antenna problem. Nope, that's not it. 4. The K3 is not in TEST mode (the TX light is on continous not flashing). I cycled TEST mode on and back off to be real sure. 5. I checked CONFIG: TX INH is off, and again cycled it through the other settings to be sure to be sure. Nope, not that. 6. I tried running the TX gain configuration through K3 Utility: the front panel shows ERR TXG and the K3 Utility reports: Unexpected response "DS@@@@@>>@°À;" to "DS;" State 153 Calibration power settled at " 0.0 W .;" There be gremlins. 7. According to the internal metering, the K3's voltage is reading a steady 13.5V and the current sits at about 1.28A on RX, increasing to about 1.62A when I hit the PTT. No change from that level when I key the paddle or speak into the mike, whether whispering, shouting or swearing. I even tried coaxing it to life, complementing it on the colour of its LCD ... 8. The power setting makes no difference: I've tried from 0 to 100W. I hear the PA relay engage around 12W as normal, and the internal power meter changes between high and low settings as expected. It's just taunting me. 9. The 20A circuit breaker on the PA is in - not that I'd have thought it would prevent the QRP level working at least. 10. I've reloaded *all* the firmware: I was using the latest beta 3.25. Reloaded that, no change. Reloaded an older version 2.78, still no change. What should I try next? I guess I need to pop the lid, look for smoke emitters and poke around at the TX driver and PA stages plus the antenna change over relay and ATU area with a multimeter but havent figured out exactly where to poke yet, nor what I should expect to see on the meter when I do ... I have other radios here and a scope. I guess I could try to trace the TX signal with the K3 set to QRP, fishing around with a wire tail on another radio's antenna socket or the scope input ... Maybe ... What do you think? 73 Gary :-( ZL2iFB ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
