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Title: WA1STH SDR Anomoly Post by: WA2SQQ on August 11, 2022, 09:08:07 AM I frequently use the WA1STH SDR. While monitoring different stations on 75m I've heard CHU (time station in Canada) in the background - very strange, but I didn't give it a second thought until now. The other day I accidentally found CHU on 5378 khz on WA1STH's SDR. What's the problem? CHU does not transmit 5378 khz. They have three assigned frequencies - 3330, 7850 & 14670. The signal have some QSB and varies with time of day so it appears to follow propagation. it's clean on the waterfall and its not distorted.
I've shared this info with another SWL group I participate in and they are also hearing it. Anyone have any explanations? Title: Re: WA1STH SDR Anomoly Post by: KB2WIG on August 11, 2022, 01:45:34 PM Probably overload SDRs front end.... just a guess. klc Title: Re: WA1STH SDR Anomoly Post by: WA2SQQ on August 14, 2022, 09:00:10 PM Listening now on 3885, and again, CHU is in the background. Earlier, listening on 6960, there was some CW. Started copying and it was stations on 40 CW. This looks like the receivers front end is experiencing some overload ….
Title: Re: WA1STH SDR Anomoly Post by: W2PFY on October 06, 2022, 03:18:01 PM At one time or another on all SDR's of that type, I have heard stations or signals coming through where they should not be. It must be the nature of the beast and not the problem of any operator that happens to have such an sdr on line from his or her QTH. It must be a matter of filtering but I am far from an expert on anything digital:) It's even more apparent when or if you have one of those 20 dollar sdr's hooked up to your own computer! (if you can get them to work) All things not being equal, when considering the low cost of these devices, they are still a lot of fun as long as you don't expect too much from them....
Title: Re: WA1STH SDR Anomoly Post by: Opcom on October 10, 2022, 05:39:28 PM Does this imply that a 'good' SDR has a tunable selective RF front end as good as something like an R390, or SX-28, NC-183, etc?
Title: Re: WA1STH SDR Anomoly Post by: W2PFY on October 12, 2022, 03:16:34 AM I think it is a situation that Depends who you ask? I had one individual tell me in person that his Flex 1500 was better than any past tube receiver he had experience with. I respected his opinion since he was a good electronics engineer with a lot of history behind him and at the same time, I have nothing to drawn upon since I have NO solid state receivers here. One thing is certain is that the solid state radios are easier to tote around:)
Title: Re: WA1STH SDR Anomoly Post by: Pete, WA2CWA on October 12, 2022, 12:00:58 PM I know this might be a weird concept, but WA1STH is a member of this forum community. Why not just send him an e-mail or PM(private message) and ask him directly or relate your issue. It can save a lot of unnecessary speculation as to the problem, solution, or whatever.
Title: Re: WA1STH SDR Anomoly Post by: WA2SQQ on October 12, 2022, 07:34:59 PM I use quite a few on line SDR’s. This incident, to date, is the only one that shows these phantom signals. I believe STH is using one of the Kiwi receivers which seem to perform very well. I’m thinking that in this case it’s some sort of front end overload, unique to his location.
Title: Re: WA1STH SDR Anomoly Post by: Pete, WA2CWA on October 12, 2022, 08:18:41 PM I use quite a few on line SDR’s. This incident, to date, is the only one that shows these phantom signals. I believe STH is using one of the Kiwi receivers which seem to perform very well. I’m thinking that in this case it’s some sort of front end overload, unique to his location. ;D assumption > a thing that is accepted as true, without proof ;D |