[Flexradio] RFI in SDR1000
I am experiencing some severe r-f problems with the flex at any external linear amp power above 100 watts carrier (AM). When the rf feedback starts it causes a repeating echo in the listeners end receiver. The first echo is the normal flex delay but then it builds on itself into multiple echos. There is no problem with my other setup in the same location using an ft1000d into a similar L4-b linear. I have used the TDK ZCAT2035 clamp on rf chokes profusely around all of the cables in and out of the flex but the problem still exists. Does anyone have a suggestion for a better choke than the tdk or other suggestions? Setup is delta44 on a 2.8gig w/512m ram. Bill Nagle [EMAIL PROTECTED]
Re: [Flexradio] RFI in SDR1000
If you are running the mic through the black box try doing it externally direct into the D-44. I had the same problem until I wired up an amplified D104 (genuine chicken choker) direct to the D-44 input and hooked the PTT to the X2 connector. If you have TWO L-4Bs I'm jealous! Net on 14329 +/- KHz this afternoon at 1900 UTC. 73, Larry K2LT Bill Nagle wrote: I am experiencing some severe r-f problems with the flex at any external linear amp power above 100 watts carrier (AM). When the rf feedback starts it causes a repeating echo in the listeners end receiver. The first echo is the normal flex delay but then it builds on itself into multiple echos. There is no problem with my other setup in the same location using an ft1000d into a similar L4-b linear. I have used the TDK ZCAT2035 clamp on rf chokes profusely around all of the cables in and out of the flex but the problem still exists. Does anyone have a suggestion for a better choke than the tdk or other suggestions? Setup is delta44 on a 2.8gig w/512m ram. Bill Nagle [EMAIL PROTECTED] ___ FlexRadio mailing list FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archive Link: http://mail.flex-radio.biz/pipermail/flexradio_flex-radio.biz/ FlexRadio Homepage: http://www.flex-radio.com
Re: [Flexradio] RFI in SDR1000
Bill, If the normal clamp-on chokes don't help, you may use double ferrite E-cores, wind several turns of cable and close together with ahdesive tape. See this: http://kotisivu.dnainternet.net/ahti/sdr-1000/USBfilt.jpg. This trick works well with my USB-to-PIO adapter proto. Larrys advice may help even better. 73, Ahti OH2RZ On 16/04/06, Bill Nagle [EMAIL PROTECTED] wrote: I am experiencing some severe r-f problems with the flex at any external linear amp power above 100 watts carrier (AM). When the rf feedback starts it causes a repeating echo in the listeners end receiver. The first echo is the normal flex delay but then it builds on itself into multiple echos. There is no problem with my other setup in the same location using an ft1000d into a similar L4-b linear. I have used the TDK ZCAT2035 clamp on rf chokes profusely around all of the cables in and out of the flex but the problem still exists. Does anyone have a suggestion for a better choke than the tdk or other suggestions? Setup is delta44 on a 2.8gig w/512m ram. Bill Nagle [EMAIL PROTECTED] ___ FlexRadio mailing list FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archive Link: http://mail.flex-radio.biz/pipermail/flexradio_flex-radio.biz/ FlexRadio Homepage: http://www.flex-radio.com
Re: [Flexradio] RFI in SDR1000
Bill, I had some RFI problems that I cured by wrapping the lines going into the SDR box around an F117-77 core using it as a common mode choke. Larry's solution is easier, so I would try it first. Also, I have found that the 3.5 mm connectors will cause an echo if not seated correctly. 73, Tom W0IVJ Larry Taft wrote: If you are running the mic through the black box try doing it externally direct into the D-44. I had the same problem until I wired up an amplified D104 (genuine chicken choker) direct to the D-44 input and hooked the PTT to the X2 connector. If you have TWO L-4Bs I'm jealous! Net on 14329 +/- KHz this afternoon at 1900 UTC. 73, Larry K2LT Bill Nagle wrote: I am experiencing some severe r-f problems with the flex at any external linear amp power above 100 watts carrier (AM). When the rf feedback starts it causes a repeating echo in the listeners end receiver. The first echo is the normal flex delay but then it builds on itself into multiple echos. There is no problem with my other setup in the same location using an ft1000d into a similar L4-b linear. I have used the TDK ZCAT2035 clamp on rf chokes profusely around all of the cables in and out of the flex but the problem still exists. Does anyone have a suggestion for a better choke than the tdk or other suggestions? Setup is delta44 on a 2.8gig w/512m ram. Bill Nagle [EMAIL PROTECTED] ___ FlexRadio mailing list FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archive Link: http://mail.flex-radio.biz/pipermail/flexradio_flex-radio.biz/ FlexRadio Homepage: http://www.flex-radio.com ___ FlexRadio mailing list FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archive Link: http://mail.flex-radio.biz/pipermail/flexradio_flex-radio.biz/ FlexRadio Homepage: http://www.flex-radio.com -- next part -- An HTML attachment was scrubbed... URL: http://mail.flex-radio.biz/pipermail/flexradio_flex-radio.biz/attachments/20060416/6f5cea5f/attachment.htm
