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FM Notch Filters / Tunable Traps

I live a mile or two from a couple 25kw FMs that cause me some overload problems on some radios. A couple years ago I bought the Sony XDR-F1HD tuner. Since being discontinued, that little tuner has been selling for 4 and 5 times what I paid Sony for a new when they were going for $50 (with a 50$ sale coupon). The sensitivity and selectivity specs are nothing short of excellent. Performance matching 'top of the line' units.
 
mofocat said:
I live a mile or two from a couple 25kw FMs that cause me some overload problems on some radios. A couple years ago I bought the Sony XDR-F1HD tuner. Since being discontinued, that little tuner has been selling for 4 and 5 times what I paid Sony for a new when they were going for $50 (with a 50$ sale coupon). The sensitivity and selectivity specs are nothing short of excellent. Performance matching 'top of the line' units.

I was reading that the Sony XDR-F1HD is a good unit, but it's impossible to find. Instead, I just purchased a vintage Yamaha T-85 I found on eBay. Many reviews praised this tuner specifically for DXing in urban areas where overload is an issue as the unit handles it well.
 
Andrew K said:
frankberry said:
I've used these Winegard FM traps. They perform well for the money. Go for it.

Thanks for everyone's input. I really appreciate it!! I'll have to wait until I get the Winegard in the mail, and I'll post my results. If anyone else has suggestions on how to fix my overloading problem, I'd appreciate anything. I'm literally 1 mile from two towers that are blasting FM stations at me and blocking the weak ones.
I have a Channel Master 700B, "Hi-Q Trap LO Band/FM". Not sure of its age. I got it (not new) 25 years ago, from a TV repair guy who sold it to me for ~$30. It has 2 vernier dials on it. The Q is so high (how high is it?) that the typical FM station's spectral energy is broader than the filter. The setting on a strong station is very sharp, but the dials read very close to each other, which helps. I couldn't use it to get Philly WRTI 90.1 at my house in Lancaster PA, because 90.3 slammed it, and the filter Q was too sharp to remove much of the 90.3 splatter. Unfortunately, the 90.3 was in almost the same direction, so a sharp azimuth antenna(s) would have required a ponderous array in a restricted neighborhood :-[
There are old notch filter kits that were made to notch out the old HBO jamming signal, way before analog scrambling for cable TV. The Q is broader, and the cap is a screwdriver trimmer. HBO was usually on low VHF and the filter tuned into the FM band as well.
The Yamaha can be modded with sharper IFs, I recommend getting a set from the guy listed on FMTunerInfo, he'll match a set to the same center (IF) freq.
Good luck, sir.
 
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