TSH511

General description

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Figure 29.

Squelch schematics

The squelch section is driven by the receiver RX1 but controls both audio buffers.

8.5

Audio buffer sections

The audio signal from an FM demodulator enters into the 6dB/octave low-pass filter for de-

emphasis. 50µs and 75µs are standard de-emphasis values.

After the de-emphasis network, the potentiometer controls the volume.

supply voltage. Under these conditions, the distortion is typically 0.3% before saturation.

The high input impedances of the audio buffers reduce the coupling capacitors to less than

0.1µF allowing space and cost saving.