Don and Dick, It does not occur with "TX Test" However, it is not any worse if I use my ALS600 at 400 Watts, or I totally disconnect the amp and just use 50 Watts out of the K3.
I think it is RF related, but only run into this problem with the HA400. I do run 450 Ohm ladder line into my shack up to my link coupled tuner but just thought that it shouldn't happen to a proper design. If I run with the front panel audio volume to zero and use the front phones jack to the HA400 I get it bad if I plug the phones into the HA400 with the HA400 volume set to about a 3. I have the same problem with the line out. If I disconnect the audio "IN" into the HA400. I still get the buzz in the phoes when I talk. So it is RF getting into the HA400. I wonder if some bypass caps in the HA400 might help. Steve, W2MY Message----- From: Don Wilhelm [mailto:[email protected]] Sent: Monday, November 16, 2009 4:33 PM To: Steven Pituch Cc: [email protected] Subject: Re: [Elecraft] K3 & Beringer HA400 Steve, Just an idea - have you tried it on LINE OUT? It may be that you are overdriving the input of the Beringer. The other possibility is that you have an RF in the Shack problem and the Beringer is reacting to the RF. Try it when connected to a dummy load or in TX TEST. If that 'fixes' the problem, you have some antenna work to do to keep the stray RF out of the shack. 73, Don W3FPR Steven Pituch wrote: > Hi All, > I tried using these two items together and am getting scratchy audio in the > headphones when I speak on USB even though the monitor is set to zero. When > I use the rear headphones out to feed the HA400 it is really bad and loud. > When I use the front headphone jack its medium loud but still not right. It > can be heard on my transmitted audio. > > I tried using a battery to power the HA400 to isolate the ground but it has > no effect. I did the "Modification Improving the Immunity of the Rear-Panel > RS232 and Audio Connectors to RF" mod, and checked to be sure that the > "Front Panel Microphone Circuit" mod had been done at the factory. I tried > also using RG 174 for the audio feed. No change. I also removed the serial > cable and had no change. > > Any suggestions would be greatly appreciated as I do need to have four > headsets on the K3 for various ham demos. > > 72 and thanks, > Steve, W2MY > > ______________________________________________________________ > 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 > ------------------------------------------------------------------------ > > > No virus found in this incoming message. > Checked by AVG - www.avg.com > Version: 9.0.707 / Virus Database: 270.14.67/2506 - Release Date: 11/16/09 02:43:00 > > No virus found in this incoming message. Checked by AVG - www.avg.com Version: 9.0.707 / Virus Database: 270.14.67/2506 - Release Date: 11/16/09 01:43:00 ______________________________________________________________ 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
