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The BEST method?

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mstechca

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Shown is a ridiculously simplified block diagram of my receiver. DET means detector (or the superregen detector to be specific).

I find that using the same value pull-up resistors in each section of my receiver does a good job, but I don't think it does the best job because there is still alot of noise in my receiver. I have played with tuning controls as well. One station that is supposed to come in clear, doesn't come in clear without a ridiculously long antenna connected to ground.

I think that the resistors must be connected in certain ways to obtain the best results. I have tried different methods, all without success.

Is it always better to have just one pull-up resistor, and have each stage hog the current from the last resistor? (in other words, all resistors in series, and between any two resistors the connection point to any stage)

Or to word it even better, Should I connect a resistor between + and the power amp, and connect a resistor from the power amp to the next amp, and do the same until I get to the detector stage?

I want to minimize noise as much as possible.
 

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MStechca,
What kind of noise? "Sssshhhhh" is noise which is different from distortion.

A properly designed audio amplifier or power amplifier doesn't produce any noise or distortion, so adding resistors to them won't make anything better.
Therefore the noise must be coming from your super-regen "detector".

Your super-regen detects AM which is prone to noise. A real FM radio uses a limiter to chop off AM and noise fluctuations in the signal and a true FM detector which also ignores noise.

Maybe your amps and power amp stages are also producing noise. Post their schematic for us to see.
 
'Pullups' is a logic term, and rarely of any relevence to an analogue circuit.

What you need to do is go back to a proper working circuit?, although a super-regen will never be particularly good anyway.
 
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