Email copied below is from a post I made in response to Jim, K9YC on the elecraft...@groups.io forum. This email has some additional observations made early this morning. The shack temperature was a New Hampshire-balmy 54F/12C.
73, Mike, K8CN -------------- begin copied email --------------------------- Thanks, Jim. Your suggestions had come to mind earlier from my recollection of your wise counsel to the various forums I read daily. Alas, the odd behavior I reported originally occurs without any transmission at all - just powered up the K3 in a cold room, started tuning the band (any band) and heard the relay clicking irregularly when either VFO A or VFO B knobs are rotated across a few kHz to tens of kHz. Anomalous behavior is independent of tuning rate. To see if I could isolate which relay(s) is (are) being activated by the VFO tuning, I went into the CONFIG menu, disabled both the PA module (KPA3A) and the ATU (KAT3), powered down and then powered back up. If the Front Panel temperature is at or below ~ 16C, then the relay clicking while tuning either VFO A or VFO B persists until the Front Panel temperature rises enough, then the clicking no longer occurs. The PA Temperature was fixed at about 13C, its cold start-up temperature, because I did not transmit or enable the ATU auto-tune. It appears that the relay clicking may be emanating from the LPF section on the RF board. I listened carefully with one ear in the open top of the K3 over the BPF section, and those relays are not changing while tuning across a single band. With the LPF section of the board now largely covered by the KPA3A PA module, I can't put a finger on individual relays to see if one particular relay is the source of the clicking. I may pull the PA module and replace the jumper block to test whether this behavior is innate to the K3/10 configuration, but I'm loathe to do that until necessary. One more observation: I've noticed on my P3 display that when the relay clicks while tuning either VFO A or VFO B, there is a narrow (in time) flat green line displayed on the waterfall. However, when I use the band switch to change bands, the P3 waterfall shows a much wider dark band until the IF signal is restored. Operationally, the clicking is only annoying for the 15 minutes or so it takes the Front Panel to warm up even if the room temperature remains frosty (54F/12C) while I'm doing these experiments. Once the Front Panel is above 17C, I can't get the relay clicking to occur while tuning either VFO A or VFO B. I may try reloading the firmware when the rig is warm - my prior MCU firmware version in the K3/10 was only one step removed from the most current version (5.67), and the DSP and FPF codes were already at the most recent versions. I am wondering if there is a communication issue on the serial control line from the MCU to the LPF relay controllers that goes away as the MCU gets warm? Thanks for the ideas, and 73, Mike, K8CN ---------------------- end copied email ----------------------------------- ______________________________________________________________ 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
