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Shure U4D Dual Diversity UHF Receiver
27
25D1062 (AG)
Service Procedures
FM Detector Quadrature Coil Alignment (Channel B)
AUDIO ANALYZER
P202
P202
P203
S201
RF SIGNAL GENERATOR
DC BLOCK
P202
P203
L304 for PCB 34A8507
P202
S201
ANTENNA A IN
ANTENNA B IN
NOTE: DC VOLTAGES ARE PRESENT
AT MOST RF TEST POINTS. USE A DC
BLOCK ON THE RF SIGNAL GENERATOR
TO PROTECT TEST EQUIPMENT.
J302
TP308
(OFF)
(OFF)
FL313
for PCB
34A8703
U310
Figure 11.
Channel B FM Detector Quadrature Coil Alignment
1. Set the rf signal generator Level to –86 dBm and the Deviation
as follows. If necessary, readjust the amplitude so HI EXT and
LO EXT lights turn off.
UA, UB,MA, MB, MC, MD: 45 kHz deviation at 1 kHz modulation
KK: 40 kHz deviation at 1 kHz modulation
II: 28 kHz deviation at 1 kHz modulation
2. Connect the rf signal generator to the ANTENNA B input.
3. Connect the audio analyzer to U310, pin 7 (TP308).
4. For PCB version 34A8507 tune L304 for maximum audio output
at TP308.For PCB version 34A8703 tune FL313 for maximum
audio output at TP308. The low limit is 250 mVrms. There is no
high limit.
Summary of Contents for U4D
Page 11: ...Shure U4D Dual Diversity UHF Receiver 10 25D1062 AG Preliminary Tests Audio Rf Board Side 2...
Page 46: ...Shure U4 UHF Diversity Receiver 25D1062 TL 45 U4 Rf Audio Printed Circuit Board Legend Side 1...
Page 47: ...Shure U4 Diversity UHF Receiver 46 25D1062 TL U4 Rf Audio Printed Circuit Board Legend Side 2...