Can anyone recommend me a crystal oscillator amplifier circuit?

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Resistanceisfutile

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I'm using a 1 MHz crystal oscillator and a crude amplitude modulation circuit (shown below), and I wanted to amplify the output. I wondered if anyone knew of a circuit I should use to amplify this?



I'm also assuming there would be a problem with harmonics flooding other frequencies, could I filter these out using active bandpass RC filters?
On another note, I recently tried using a passive, variable resistor with a capacitor (RC) filter with an MP3 player and some headphones - I got nothing. If I amplified the output of the filter, would I get any filtered audio out of the headphones (assuming I wasn't filtering out all the sound)?
 

Your circuit is really crude! This is not the good way to obtain a 1 MHz AM modulated signal.

You should feed 5 VDC to the crystal oscillator, and use a buffer amplifier in which you can apply the audio modulation.
For 1 MHz you can use a common FET amplifier , input to gate and a LC resonant circuit in the drain. Then connect your audio transformer to the DC power supply feeding FET drain. An audio amplifier may be needed to apply a larger audio voltage to the buffer amplifier.

Filtering the 1 MHz output is best done by a coupled LC circuit pass-band filter. RC filters are better suited for audio range.

I can see you do not like to learn the basics. Connecting "some" RC filter to "some" headphones may not work as for a good filter there is good to know the source and load impedances. You apparently have no idea I speak about.
 

So what are the "basics"? You mentioned I should take account of load and source impedance, are there any things I need to be aware of when it comes to radio circuits?
 

So what are the "basics"? You mentioned I should take account of load and source impedance, are there any things I need to be aware of when it comes to radio circuits?

I would recommend the ARRL Radio Amateur's Handbook, any year issue. There are basics for filters, electronic circuits and also how to design simple transmitters, receivers, modulators you can imagine.
 

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