I am glad it is not affecting you Lexa - possibly just my K3. I noticed it while using the key to generate a carrier in SSB mode to set the power level - a pulse of all LEDs lighting up on the XV50. Using the scope at the 28MHz IF I could see the spikes clearly. I would estimate 2 to 3 times the voltage for 1mW, so spikes of up to around 10mW.
These were in both SSB and CW. Also FM for that matter. It only occurred for the first transmission for a band/mode/power setting. I could get it to do it by turning the power knob key down. I downgraded to the stable firmware and the problem went away so I doubt it is a hardware problem. I will try upgrading again and see if it comes back, that is the risk of using a beta. It may be a simple firmware glitch particular to the settings I had, or it could be a problem with my ALC only revealed by the new beta ALC implementation. Alexandr Kobranov wrote: > > Hi Mike, > > your problem is in SSB or also in CW mode or in both? > > There are no visible spikes on DB6NT 144MHz transverter/25W out. > Firmware 2.10 now implemented. > > 73! > Lexa, ok1dst > > AD6XY - Mike napsal(a): >> Thanks for the Email suggestions. >> >> Setting tune power back to normal did not fix it. It fixed it for one >> cycle. >> I also had my K3 lockup in the config menu. I suspect some problem with >> the >> new beta firmware to be the cause, possibly corrupted memory or something >> like that. I have gone back to the old firmware and the system is >> working. >> The overshoots are still there as you adjust the power control but they >> are >> much smaller. >> >> Mike >> >> >> >> AD6XY - Mike wrote: >>> I have come across a problem with my K3 driving an XV50 converted to >>> 70MHz. >>> >>> The K3 low level output from the KXV3 produces high power spikes before >>> settling to the correct level - which it then holds until you change >>> mode, >>> or power setting. It also produces spikes at full power ( a few mW) as >>> you >>> turn the power knob. When I originally tested the transverter interface, >>> I >>> used an analogue power meter, so I would not see these spikes. I can see >>> them clearly on my oscilloscope for a few fractions of a second before >>> the >>> ALC acts. >>> >>> The effect is of course for the transverter to over drive and then >>> settle >>> back. Obviously I am doing something wrong here but I am not sure what >>> it >>> is. The K2 does not do this but it is making transverter operation >>> impossible with my K3 until I can find out how to fix it. >>> >>> The curious thing is the way the spikes appear as you adjust power. It >>> is >>> like the CPU is forgetting the ALC setting, reading the op-amp output, >>> thinking for a bit and then setting the correct gain. I must have some >>> setting set incorrectly. >>> >>> Mike >>> >>> PS >>> >>> The K3 also suffers from the same transverter failure mode as the K2 - >>> if >>> you power off the radio in a transverter band, the transverter stays on >>> in >>> transmit mode because of the way the PTT works and because the K3 does >>> not >>> send an "off" command on the auxbus before shutting down. The result is >>> a >>> very hot transverter power amplifier module the next morning. Perhaps we >>> could fix this using one of the digital outputs? >>> >>> >>> >> > _______________________________________________ > Elecraft mailing list > Post to: Elecraft@mailman.qth.net > You must be a subscriber to post to the list. > Subscriber Info (Addr. Change, sub, unsub etc.): > http://mailman.qth.net/mailman/listinfo/elecraft > > Help: http://mailman.qth.net/subscribers.htm > Elecraft web page: http://www.elecraft.com > > -- View this message in context: http://www.nabble.com/K3-Transverter-drive-problem-tp18203550p18211075.html Sent from the Elecraft mailing list archive at Nabble.com. _______________________________________________ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
