Block broadcast FM interference with an FM notch filter

I noticed recently that I have some interference on the aviation bands with my RTL-SDR. After tinkering with it for a bit, I noticed it was coming from a local 50,000 watt FM broadcast station within one mile of my home. I looked around online and it was recommended to get an FM notch filter. That would hopefully block out the FM broadcast band signals (88-108 MHz) getting into my SDR.

I ordered one made by Nooelec called the Flamingo v2 FM Notch Filter. It’s pretty simple to hook up. You plug in your antenna on one side and the other side goes to your SDR. It comes with an adapter to hook it up directly to your SDR which was nice. I immediately noticed the 50,000 watt FM station was gone from both the aviation band as well as from the FM broadcast band. Not bad for $22!

One thing I noticed is that the filtering drops off around 105.9-107.9 MHz. While stations aren’t as a strong in that range, they’re definitely visible on the waterfall. So if you have a super local strong station in that area of the band this filter might not solve your FM interference. Still, for $22 it’s definitely worth a shot.

If you’re interested in buying this FM notch filter, I’d appreciate it if you went through my Amazon affiliate link below. There is no extra cost to you and I receive a small commission which helps support my content. Thanks!

Flamingo v2 FM Notch Filter: https://amzn.to/3ZEHVu9
RTL-SDR v3 SDR (w/antenna): https://amzn.to/3I9rcbP
RTL-SDR v3 SDR (dongle only): https://amzn.to/3XmNyem

I also made a video demonstrating this filter hooked up to my RTL-SDR. Check it out and let me know if you have any questions or comments. Thanks!

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