Shure U4D, Service Manual

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Shure U4D Dual Diversity UHF Receiver
24
25D1062 (AG)
Service Procedures
Second Mixer Coil Alignment (Channel A)
L313
P202 P202
P203
S201
RF SIGNAL GENERATOR
ANTENNA A IN
P202
P202
P203
S201
ANTENNA B IN
U303 / U315
DC VOLTMETER
PIN 8 / PIN 17
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 8. Channel A Second Mixer Coil Alignment
1. Change the rf input level to –105 dBm.
2. Adjust L313 for maximum dc voltage at U303 pin 8 for PCB ver-
sion 34A8507 or at U315 pin 17 for PCB version 34A8703.