On Mon, 18 Jan 2010 04:21:16 +0000, Jim Harris <[email protected]> wrote: Did You check your VOX to make sure it was off? Tom, N5GE
[email protected] K3 #806 with SUB RX, K3 #1055, PR6, XV144, XV432, KRC2, W1, 2 W2's and other small kits 1 K144XV on order http://www.n5ge.com http://www.swotrc.net > >Hi folks, > >While phone contesting yesterday I found there is audio feedback from >headphones/external speakers through the microphone without the PTT being >pressed. Monitor level was initially set at about 15. I was using a Heil >BM-10ic headphone through the front panel with bias turned on. They have tiny >ear pads that could easily let an amount of noise slip past to the microphone. > The audio line out on my K3 back panel goes to a computer which has garden >variety speakers hooked to it's audio out. > >On the radio I had the AF control turned most of the way up and was riding the >RF (IF) gain. NR was on with a setting of F1-2. I found that when the RF >gain was turned up something like half way or more (depending on signal level) >the audio level would creep up as though AGC was pumping. If the gain was >further increased the characteristic howl of feedback resulted. Remember all >this was occurring without PTT (no PTT light). I would have thought the >microphone would be dead without PTT. > >I turned down the monitor to 8 and the feedback was not as much but was still >present. Finally I moved the volume control slider for the computer speakers >to the bottom and that eliminated the feedback. > >I'm very surprised to find a microphone connected to the K3 is live and that >the audio is being feed to the audio outputs without the PTT being pressed >resulting in the described feedback. That is disappointing because it limits >the ways that I can use my radio. I'm wondering if this may be the source of >some noise comments here on the reflector. Does anyone else have any >experience with this or any constructive comments? > >Have a good day and 73. > >Jim, W0EM > > > >______________________________________________________________ >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
