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Old May 27th 06, 03:39 PM posted to rec.radio.amateur.antenna
g. beat
 
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Default Please Help me urgently

"mavihot" wrote in message
ups.com...
Hello,

I can not handle a problem which is about AGC. Please help me about
that. The conditions are;
It is required to design and implement an AGC circuit
with the following specifcations:

1. Amplitude of the input voltage may vary between 10 mVpp and 50 mVpp.

2. Amplitude of the output voltage should be in the range 0.9 Vpp
and1.1 V
pp for the input signals with amplitudes stated above.

3. Output impedance of the ampliŻer should be smaller than 2 k*.

4. The circuit should be able to amplify the signals having frequencies
between 500 Hz and 10000 Hz.

The amplifer designed should be a single transistor amplifer in the
common-emitter form for BJT amplifers or common-source form for the
FET amplifers. However, it can be used extra transistors for making the
amplifer an adjustable gain amplifer.

And the AGC should be composed of 2 parts adjustable gain part and
feedback part.

Please help me urgently to design this problem. Thanks...
==========================================
This sounds like a class assignment for an electronics design course.

The circuit should be able to amplify the signals having frequencies
between 500 Hz and 10000 Hz.


OK, its an "audio frequency" related amplifier design. Additional
requirement
that the single transistor amplifier be a common-emitter form for BJT
amplifiers
or common-source form for FET amplifier designs

3. Output impedance of the amplifier should be smaller than 2 k ohms*.


Speakers are 4, 8 or 16 ohm loads; 600 ohms is fairly standard in broadcast;
Original crystal set headphones (Trimm - vintage WW2) were 2000 ohms

Amplitude of the output voltage should be in the range 0.9 Vpp and 1.1 Vpp

for the input voltage that may vary between 10 mVpp and 50 mVpp.

Standard amplifier with an AGC circuit - added requirements that the AGC
should have
both an adjustable gain and feedback control.

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