This could be from a noisy switching power supply. I had the kind of noise as described and changing power supplies cleared it up. A good linear type power supply may help. No such noise as described now, so not characteristic of a Flex Radio.
Could even be noise from a close by wall wort supply, even picked up with the dummy load. A mismatched antenna will not cause noise on receive. By using a closer matched antenna you are increasing the atmospheric noise and general signals to cover up the possible power supply hash noise. 73. John. N3WT. On Nov 30, 2012, at 8:46 AM, Drax Felton <draxfel...@gmail.com> wrote: > I see this all the time too. Especially pronounced on 6 meters where I can > chase these but not tune them in as they move. > > I assumed that all radios have glitches the Flex just lets you see them at > -130db > > > Sent from my iPhone > > On Nov 29, 2012, at 5:23 PM, Steve Sterling <f...@sgsterling.com> wrote: > >> My Flex 5000 receivers do not like off-normal (50 ohm) antenna loads. Unplug >> the antenna, or put an unmatched antenna on them and they create all kinds >> of weird oscillations, big wide humps across the spectrum. >> >> Examples: >> >> * short the receiver inputs, all OK, baseline down there below >> -135dbm, all bands >> * put the inputs on 50 ohm dummy load, all OK, all bands >> * open the antenna input (pull the line) and it goes nuts, >> * hook my SteppIR up, but tuned to a different band, many times (not >> all) the receivers go nuts; same with mistuned G5RV >> * tune any of the antennas anywhere close to 50 ohms-- receivers >> behave well, best I can tell (noise may be covering up any >> oscillations that are well below my local noise floor). >> >> I just figured this is the way these receivers worked, and they don't effect >> my operations. Is the antenna you are using a good match? >> >> Steve WA7DUH >> >> On 11/29/2012 1:22 PM, py...@terra.com.br wrote: >>> Been playing with JT65HF which on 15m is confined to the 2KHz in USB >>> on 21.076. I-ve noticed a broad noise covering just about all of that >>> segment and imagined it to be one more of the many noises generated by >>> a big city, but the other day I left the antenna disconnected and the >>> noise is still there! Wonder if anyone else has noticed this and if >>> there is a way to make it go away or move frequency! I´m using PSDR >>> 2.3.5 / Windows 7 on a Flex3000 and have tried other buffer and >>> scanning rate settings, but nothing seemed to make a difference. It is >>> -126dB without an antenna and has a cyclic sound to it.73 Rolf, PY1RO >>> _______________________________________________ >>> FlexRadio Systems Mailing List >>> FlexRadio@flex-radio.biz >>> 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.flexradio.com/ Homepage: >>> http://www.flexradio.com/ >> >> _______________________________________________ >> FlexRadio Systems Mailing List >> FlexRadio@flex-radio.biz >> 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.flexradio.com/ Homepage: http://www.flexradio.com/ > > _______________________________________________ > FlexRadio Systems Mailing List > FlexRadio@flex-radio.biz > 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.flexradio.com/ Homepage: http://www.flexradio.com/ _______________________________________________ FlexRadio Systems Mailing List FlexRadio@flex-radio.biz 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.flexradio.com/ Homepage: http://www.flexradio.com/
