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Author Topic: Parallel LC MW Notch Filter  (Read 944 times)

Offline ChrisSmolinski

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Parallel LC MW Notch Filter
« on: December 30, 2021, 1320 UTC »
A quick and dirty parallel LC notch filter to cut down local pest WHVR 1280 AM by about 20 dB on the 250 ft V Beam antenna, it was overloading the KiwiSDR now and then. Made with some junkbox components: 1800/680 pF mica caps in parallel with about 6.2 uH from the variable inductor.

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Chris Smolinski
Westminster, MD
eQSLs appreciated! csmolinski@blackcatsystems.com
netSDR / AFE822x / AirSpy HF+ / KiwiSDR / 900 ft Horz skyloop / 500 ft NE beverage / 250 ft V Beam / 58 ft T2FD / 120 ft T2FD / 400 ft south beverage / 43m, 20m, 10m  dipoles / Crossed Parallel Loop / Discone in a tree

Offline M R I

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Re: Parallel LC MW Notch Filter
« Reply #1 on: December 30, 2021, 1909 UTC »
Nice. Just enough to bring down the signal around one frequency.
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Offline ~SIGINT~

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Re: Parallel LC MW Notch Filter
« Reply #2 on: December 30, 2021, 2349 UTC »
OMG - look at all that connector loss and potential leakage :)  Sorry Chris, I was a broadcast engineer, facility designer and also engineered comm circuits for the military - LOL
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