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PROJECTS AND KITS (02)

A Speech Processor for the FT-817 - Information from eHam and Ok1CDJ



Speech Compressor for FT-817
OK1CDJ


FT-817 doesn't have any type of speech processing built-in.This audio speech compressor is designed with the Analog Devices SSM2165 device. The circuit is small enough that it can be built into the microphone.Gain of whole circuit is about 18dB, compression ratio is set by R1 and can be varied from 1:1 to 15:1. Output level can be set by R2, R3. Power consumption is around 7.5mA. Compressor is supplied directly from microphone, no external power supply is needed.

Speech
                          Compressor for FT817 etc
Fig. 1 - schematic

Speech Compressor
                          for FT817 etc

Compressor is completely build using SMT on small board (15x11mm).
Fig. 2 - PCB
Part list:
C1 22uF /10V size B
C2 10uF /10V size B
C3 10uF /10V size B
C4 100nF 0805
C5 100nF 0805
C6 1nF 0805
C7 100nF 0805
IC1 SSM2165 SO08
R1 180k 0805
R2 22k 0805



DYC-817 Speech Processor / Compressor






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