Motorola HT Series Service Manual page 50


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Rx-SW
Tx-SW
(U201 Pin 28)
VSF
Steer Line
Voltage
(VCTRL)
RX RX VCO
Tank Circuit
TX TX VCO
Tank Circuit
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Pin 20
Pin 7
TX/RX/BS
Pin 13
Switching Network
Vcc-Superfilter
Pin 3
Collector/RF in
Pin 4
Pin 5 RX
Rx Active
Pin 6
Pin 16 TX
Tx Active
Pin 15
Vsens
Circuit
Pin 18
Vcc-Logic
VSF
(U201 Pin 28)
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Table 2-7
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Figure 2-23
Level Shifter
Network
TRB_IN
Pin 19
Presc
U250
VCOBIC
RX
Bias
TX
Bias
Pin 2 Pin 1 Pins 9,11,17
Rx-I adjust Tx-I adjust
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5V
AUX3 (U201 Pin 2)
AUX4 (U201 Pin 3)
Prescaler Out
Pin 12
U201 Pin 32
LO RF INJECTION
Pin 8
Injection
Amplifier
VSF
Pin 14
(U201 Pin 28)
VCC Buffers
Pin 10
TX RF Injection
Buffer
Amplifier
75%