Clay, I have no idea if this will make any difference, but you (really, everyone) should upgrade to the latest firmware if you have not done so and definitely upgrade to the latest Firewire driver (3.4.0.5254) and it is much improved over the 3.2.0 version. After doing that let us know if that made a difference.
-Tim -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Clay W7CE Sent: Friday, June 05, 2009 7:10 PM To: [email protected] Subject: [SPAM] [Flexradio] Increased receive noise level on 6M after CW Transmit I see an interesting behavior on my Flex 5000A when transmitting 6M CW. When I transmit on 6M CW, either by pushing the CW key or the PTT on the rear panel (no output power in this case), and then go back to receive, the panadapter, S-Meter and audio output all show a 9 dB increase in receive noise level for about 5.5 seconds at which time everything returns to normal. This occurs in both CWU and CWL, and in Tune, but no other modes as far as I can tell. It also doesn't matter what the bandwidth is set to. I normally use an external 26 db gain preamp on 6M (connected to RX1 in/out loop). If I disable the external preamp, I still see the behavior, although the increased noise level is only about 2 dB. Next I connected a dummy load and repeated the experiment. Now the noise level increases by 15 dB for about 5.5 seconds (still about 2 dB with the preamp disabled). I assume that the larger increase is because I show a much lower noise level when connected to the dummy load vs. the antenna. I considered the possibility that the preamp was somehow responsible, so I disconnected it from the 5000A and still see about a 2 dB increase in noise after CW transmit. I don't observe this behavior on the other bands. It is repeatable every time on 6M and always lasts for about 5.5 seconds. Anyone have an idea what's causing this? BTW, I'm running PowerSDR 1.16.1, with Flex Driver 3.2.0 build 1556. 73, Clay W7CE _______________________________________________ FlexRadio Systems Mailing List [email protected] http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archives: http://www.mail-archive.com/flexradio%40flex-radio.biz/ Knowledge Base: http://kc.flex-radio.com/ Homepage: http://www.flex-radio.com/ _______________________________________________ FlexRadio Systems Mailing List [email protected] http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archives: http://www.mail-archive.com/flexradio%40flex-radio.biz/ Knowledge Base: http://kc.flex-radio.com/ Homepage: http://www.flex-radio.com/
