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Frequency detection

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New Member
Hello! I am new to the forums and pretty new to electronics. I am trying to figure out the best way to detect a signal with fc 100k and a 30k passband. I understand the concept behind obtaining a signal using an antenna, I guess the real question is what is the best way to process the signal (op amp, transistor, LC circuits)? Thank you in advance for some direction!


Well-Known Member
Most Helpful Member
Active bandpass filter consisting of opamp, resistors, and capacitors would work, but how steep do you want the edges of the filter to be? 2, 4, 6,... Poles?

How much gain?

Sounds like this is a TRF receiver?

You would have to use opamps that have a GBW product in excess of 10Mhz, which lets out a lot of garden variety opamps (i.e. no 741s).
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