Kenwood TS-820S Instruction Manual page 29

standard oscillator to produce a voltage to control VCO (vol-
tage controlled oscillator). It also forms a full electronic IF
shift loop using an external carrier signal. The VCO unit is
composed of FET type oscillators for each band, buffer am-
plifier circuit, and the oscillator shut off circuit at the time of
fault of the PLL circuit. The oscillator frequency is controlled
by the control voltage from the PD Board. The bands of
both units can be selected by means of the diode switches.
COUNTER ASS'Y UNIT (X60-1020-00)
(TS-a20S TYPE ONLY)
This unit is composed of the counter mixer board that
produces operating frequencies by mixing the VCO output
(local oscillator signal for the mixer) with carrier signal. and
the counter board that counts the frequencies in digits
These units are housed in a rigid shielding case Since the
frequencies are read by synthesizing all the local oscillator
signals. accurate operating frequencies are always counted
under any operating conditions. The counter output is pick-
ed up as a signal to drive the indicating tubes and is fed to
the display unit.
Counter Ass'y Unit
Fig. 17 Counter Ass'y Unit
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