There is a voltage output point for the OTP IC voice circuit (FK 13XX)The power amplifier circuit uses IC Power Amp No. TDA2030, an OTL operation. This circuit is able to amplify signal from the OTP IC voice circuit.
Total harmonic distortion : 0.03% (0.1-14W/1kHz)
Frequency response : 20Hz to 20kHz (-3dB)
Power supply : 12VDC./800mA. max.
Output power : 8W @ 4
Sound level is adjustable by trimmer potentiometer.