Shure U4D, Service Manual

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Shure U4D Dual Diversity UHF Receiver
28
25D1062 (AG)
Service Procedures
Second Mixer Coil Adjustment (Channel B)
P202
P203
U313 / U316
L324
P202
S201
ANTENNA A IN ANTENNA B IN
DC VOLTMETER
P202 P202
P203
S201
PIN 8 / PIN 17
RF SIGNAL GENERATOR
DC BLOCK
NOTE: DC VOLTAGES ARE PRESENT
AT MOST RF TEST POINTS. USE A DC
BLOCK ON THE RF SIGNAL GENERATOR
TO PROTECT TEST EQUIPMENT.
(OFF) (OFF)
J302
Figure 12. Channel B Second Mixer Coil Adjustment Connections
1. Change the rf input level to –105 dBm.
2. Adjust L324 for maximum dc voltage at U313 pin 8 for PCB
version 34A8507 or at U316 pin 17 for PCB version 34A8703.