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fm preamp circuit

 
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deepak007



Joined: 20 Sep 2007
Posts: 61
Post05 Jul 2008 20:51   fm preamp circuit
hello

can anybody give me a FM (rf) preamplifier circuit to increase the sensitivity of an ordinary store bought fm receiver? please help.
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Audioguru



Joined: 19 Jan 2008
Posts: 349
Helped: 22
Location: Canada
Post06 Jul 2008 2:22   fm preamp circuit
If you live near civilization that has many FM stations then an RF preamp will be very overloaded by all the strong signals.
A good radio tunes a certain frequency first then amplifies it. Then it uses automatic-gain-control so that the single selected station does not overload it.
Get a better radio.
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deepak007



Joined: 20 Sep 2007
Posts: 61
Post06 Jul 2008 5:12   Re: fm preamp circuit
no problem. i will use diodes in the front end to prevent overloading. so, please give me a schematic.
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Audioguru



Joined: 19 Jan 2008
Posts: 349
Helped: 22
Location: Canada
Post06 Jul 2008 5:43   fm preamp circuit
Diodes won't prevent overload.
The forward voltage of silicon diodes is hundreds of times higher than strong local signals.

Buy a TV RF amplifier and see how it overloads.
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zlatkoMM



Joined: 04 Apr 2008
Posts: 111
Helped: 3
Location: Croatia
Post06 Jul 2008 10:33   Re: fm preamp circuit
Oh man ...guy need shematic only so here is one i think that is easy.

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