This is an AM demodulator which is not affected by phase errors in the demodulated signal. Phase error is a type of error commonly found in simple
diode/low pass filter demodulators. At the input stage is an AC amplifier which is adjustable through P1.
A1 and A3 are the rectifiers that charges C6 with the maximum signal voltage. The analog switches are controlled by a clock signal.
The clock signal is derived from the carrier frequency. In this way the sampler can be applied in different devices like facsimile,
radio and speed processors since its clock frequency is directly controlled by the received carrier frequency.
Electronic Circuits volume 1.0 - Circuit Nr. 11
The complete data of the electronic circuit described above can be found in the following book and is available from Amazon.com.
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