Alinco DJ-195, Service Manual

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6. Tone Encoder
The CPU (IC9) is equipped with an internal tone encoder.The tone signal (67.0
to 250.3Hz) is output from pin 9 of the CPU to the varicap (D3) of the VCO for
modulation.
7. DCS Encoder
The CPU (IC9) is equipped with an internal DCS code encoder. The code (023
to 754) is output from pin 9 of the CPU to the varicap (D3) of the PLL reference
oscillator. When DCS is ON, DCS MUTE circuit (Q15-ON, Q18-ON, Q16-OFF)
works. The modulation activates in X1 side only.
8. CTCSS, DCS Decoder
The voice band of the AF output signal from pin 10 of IC5 is cut by sharp active
filter IC8 (VCVS) and amplified, then led to pin 4 of CPU. The input signal is
compared with the programmed tone frequency code in the CPU. The squelch
will open when they match.
9. Clock Shift
In the unlikely event that CPU clock noise is present on a particular operating
frequency programmed into the radio, you can shift the CPU clock frequency to
avoid the CPU clock-noise. The output signal from pin 31 of the CPU turns on
Q30. Then the oscillation frequency of X2 will be shifted about 300 ppm.
5) M3826M8L
***
GP (XA0644)
CPU
Terminal Connection
(TOP VIEW)