Kenwood TM-D700A Service Manual

TM-D700A/E
CIRCUIT DESCRIPTION
10
3-3.APC circuit
The Automatic transmission Power Control(APC) circuit has
a differential amplifier (\C200) that compares the DC voltage
generated by detecting part of the transmission output using
diodes (VHF: D18, D19; UHF: D317, D318) with the reference
D18
:
voltage output from the CPU. The output signal is amplified by
Q209 and Q208 and fed to the power module to keep
transmission output constant.
VHF AW
D19
k DC AMP
I
comparator
PCA
DC
AMP
1C200 2Se4617
TA75S01F
(R)
D317
k t CPU
UHF AM,
0318
:
Fig.11 APC circuit
3-4.Overheating protection circuit
To protect from the thermal destruction of the power
module, the voltage of the thermistor (TH1) near the power
module is monitored by the CPU (IC604). If it becomes high
temperature,
the
APC
voltage
is
controlled
to
cool
down
the
temperature.

Kenwood TM-D700A Specifications

General

Brand	Kenwood
Model	TM-D700A
Category	Transceiver
Language	English