Those knobs are actual potentiometers, not encoders, acting as voltage dividers off a fixed voltage, which are followed an an A/D chip which converts the wipe voltage to a three digit number which is multiplexed and sent to the MPU. The audio does NOT flow through the pot. The setting of the pot is turned into numerical advice to the MPU.
If the voltage on the pot wipe goes out of range or the wipe loses contact, the number sent to the MPU will be weird. It won't be scratchy like an analog volume pot gone bad, just go to unpredictable and undesired volume settings. The pots are not killer to change out, but you need moderate to good soldering skills to do it. I bunged one and had to change it out. Done this on both my K2 and K3 now. 73, Guy. On Sun, Jul 8, 2012 at 10:40 AM, Matt Zilmer <[email protected]> wrote: > Many K3 users have seen this same rotation problem with the AF/SUB and > RF/SUB controls. Try adjusting the set screw(s). If that doesn't > work, you may need to contact support for new ones. With early K3s, > there were some problems with these controls. > > Not sure about your audio/volume problem though. I'd contact support > on this too. > > 73, > matt W6NIA > > On Sun, 08 Jul 2012 08:45:35 -0400, you wrote: > >>I suddenly came up with several problems related to audio volume on my >>K3, MCU 4.51. >> >>I was listening on USB with slow AGC and I noticed that the volume would >>suddenly drop and remain low until I hit the T/R button, whereupon it >>would come back again, and then disappear. I switched to fast AGC and >>the problem diminished but did not disappear. So I reached for the >>audio volume control and discovered that it now turns 360 degrees >>without a stop, although there is a slight detent at the regular >>stopping point. I tried to turn AGC off, and although the display >>indicates that it is off, there appears to be no increase in volume. I >>now feel that the volume is lower than it was when I first built the unit. >> >>There may be some troubleshooting to do here. I notice this less with >>strong signals. I guess I would like to know what to do about the >>rotation first, and then pursue the overall volume problem. >> >>Thank you, >> >>Jan, KX2A >> >>______________________________________________________________ >>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 > ______________________________________________________________ > 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 ______________________________________________________________ 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

