Thanks Don, With the nut loose, it is much less intermittent. When it does hang up, a tap on the back of the left side panel causes the 2Mhz birdie to return, so I think I'll order a replacement for K8 just in case it's been damaged.
With hands like catcher's mitts,"Beefing" fasteners is always an issue for me... The 80M high current behavior I observed is exactly what you describe. 73, Jim KO5V -----Original Message----- >From: Don Wilhelm <[email protected]> >Sent: Mar 2, 2019 1:04 PM >To: Jim KO5V <[email protected]>, Elecraft List <[email protected]> >Subject: Re: [Elecraft] K2: Flaky 160M switching > >Jim, > >Loosen the nut on the BNC connector or remove it entirely. Since the >BNC jack is soldered to the board, the nut is only there for "pretty" >All will work fine without the nut. The nut in any case should only be >a bit more than finger tight. "Beefing" the nut up tight can damage the >BNC connector (same for the key jack). > >Yes, tightening the nut up tight is likely bending the RF Board. > >Check for the possibility that the rear panel is bent a bit in the >vicinity of the hole for the BNC jack. > >As for the high current on 80 meters after moving from a non-functioning >160 meters, that is not unusual. The Drive to the RF Chain is maxed out >on 160 and when you move to 80, it will not be reset with a TUNE - >normal keying or speech will quickly correct it, but not TUNE until you >exit and re-enter TUNE. > >73, >Don W3FPR > >On 3/2/2019 2:30 PM, Jim KO5V wrote: >> After removing and replacing the heatsink panel to install an SMA connector >> for an IF-out port, >> 160M is working intermittently. I think I have narrowed it down to a problem >> with the antenna's >> BNC connector - It appears to be just slightly spaced away from the inside >> of the back panel, >> so when its nut is tightened up, it must be flexing the RF board enough to >> affect K8. I've loosened >> up the 2d connectors, to try and bring the connector/RF board into better >> alignment with the heatsink >> panel, but every time I tighten up the BNC's nut, 160 eventually dies (I >> listen to the birdie at 2Mhz). >> >> When I switch from a working 160M to 80M and then "tune", 80M gives a >> "hi-Current" error, and I >> measure >20W on my external meter. A second "tune", and 80M is back to >> normal. Switching back to 160M, >> I find the birdie gone (and no power out). Switching to 160M from a >> higher-frequency band usually finds 160M >> working (but not always). >> >> I have touched up the solder joints on all components involved with K8 and >> the BNC on the RF board, and all >> of the joints on the 160M board. >> >> So, I am going to place a shim between the BNC connector, and the heatsink >> panel and see what happens. Does >> anyone have any other suggestions? I'm not sure K8 is bad, but maybe the BNC >> might be? ______________________________________________________________ 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
