Anybody have a chance to try this? Would be useful to know if someone else cannot. Would be equally useful to know if someone can. Still waiting to hear back from Elecraft.
Thanks, Drew n7da On Fri, Aug 21, 2020 at 3:22 PM Drew Arnett <arnett.d...@gmail.com> wrote: > > Oscilloscope "screenshot" of the offending waveform: > > https://drive.google.com/drive/folders/1-g9Met098lhncAcMtAAOvxWFDjf0NU_w?usp=sharing > > Can anyone try to reproduce this to rule out or confirm my suspicion > it might be caused by firmware bug? > > You can imagine how fast I knocked my headphones off! :-O :-) > > Thanks and best regards, > > Drew > n7da > > On Wed, Aug 19, 2020 at 2:49 PM Drew Arnett <arnett.d...@gmail.com> wrote: > > > > Hi, > > > > Weird problem. Anyone else try this and do or don't see this? > > > > Just got my KX3 back from repair. This included an upgrade to the > > latest firmware. (Makes sense. Requirement for production test. I > > hadn't upgraded to the very latest, because I had no need for the > > latest improvements.) > > > > Set the radio back up for 10368 to 50 MHz transverter use on XVTR1 > > band. Now, if I power up the radio when it was shut down on the XVTR > > band, there is a crazy loud buzz on the audio output (and > > corresponding response of the S meter.) If I switch to any other > > non-XVTR band and then power up, no problem even if switching then to > > the XVTR band. > > > > FW is now 2.90/1.52I got the radio back just before the 10 GHz > > contest, so only made minimal changes to settings from the cleared > > state it came back in. Changes made: > > AFX mode off (was delay) > > ATU bypass (can't remember if it came back this way or not. XVTR is > > good 50 ohm load.) > > BAT CHG off (was not inst) > > BKLIGHT off (was on) > > MIC BIAS off (I think came back on; used dynamic mic during contest) > > MIC BTN Ptt (was up/down) > > TX DLY 10 (was 5. abundance of caution as 5 is more than enough for > > the 10 GHz rig I'm running) > > XV1 on > > XV1 RF 10368 > > XV1 IF 50 > > XV1 PWR 0.1 > > XV1 OFS (set in field) 1.20 > > XV1 ADR trn1 > > set the clock. :-) > > turned on the hidden in the menus CW-in-SSB feature > > > > I know I turned on or off a couple of front panel things as they left > > it. Don't remember. Stuff like vox, pre, nr or nb. Definitely > > adjusted mic gain and compression and keyer speed. :-) > > > > RX ISO changed to on during the contest, but problem occurs with it on or > > off > > > > What does the headphone jack output look like? Power up in bad state. > > Set volume control to 20. With no load other than 10X scope probe, > > the AC component is identical for left and right. Tip has about 0 V > > DC offset. Ring has about + 0.5 V DC offset. AC component looks like > > a the differential of a square wave. Peak to peak amplitude is 220 > > mV. (This follows volume control. Didn't check to see if DC offset > > follows volume control.) 12.2 millisecond repetition rate for > > positive and negative pulses. Negative pulse leads positive pulse by > > 2.2 ms, so 10 ms from positive pulse to negative. Very small AC > > ripple on that with a period of about 0.4 ms. > > > > I was very happy to find a sequence to avoid the problem (as described > > above.) To trouble shoot, I tried to rule out a number of things. > > Unplugged ALL cables from the KX3. That did not resolve. Tried > > external 12.4 V (battery on hand) and internal battery removed. Tried > > internal battery (charged) and nothing plugged in. No dice. > > > > Given that it's just back from repair, that sequencing gets it in a > > bad state, FW was upgraded to a new version, and audio path goes > > through FW, seems reasonable to ask if this is a known FW issue or if > > someone can try to reproduce this. > > > > Hoping to figure this out before the Sept VHF, the Sept 10 GHz contest > > weekend, and of course the HF contests coming up later this fall. :-) > > With my workaround, I was able to participate in the Aug 10 GHz > > weekend without interruption. I ran a W1GHZ XVTR barefoot (+5 dBm > > Pout) for best DX of 379 km. How much fun can you have with a KX3? > > Lots! :-) > > > > Thanks and best regards, > > > > Drew > > n7da ______________________________________________________________ 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 Message delivered to arch...@mail-archive.com
