Shure UC2, Руководство по обслуживанию

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Shure UC2 Hand-Held UHF Transmitter
Service Procedures 21 25A1044 (RI)
Deviation Adjustment Voltage: Using an SC4 IF Receiver
AUDIO ANALYZER
TEST HEAD
AUDIO
SIDE 1
TPA4
(U201, PIN 7)
UC2 Transmitter Audio Analyzer
Power: +9 Vdc Measurement: AC level
Gain: Minimum Frequency Output: 1 kHz
Filters:
Low-Pass (30 kHz): ON
High-Pass (400 Hz): ON
Figure 13. Deviation Adjustment Voltage Test Set-Up,
Steps 1 through 5, Using a Modified SC4 IF Receiver
1. Disconnect the rf signal generator from the SC4 IF receiver.
2. Set the SC4 tone key switch on the SC4 front panel to ON.
3. Connect the audio analyzer output to the MIC input of the
transmitter, using the test head or clip leads to the gold spring
contacts.
4. Turn the UC2 power back ON.
5. Adjust the audio input level using the audio analyzer output to
measure the following at TPA4 (U201, pin 7) :
UA MB, MC JA, JB KK
–6.8 dBu
±
0.2 dB
(354 mV
±
1 mV)
– 16.3 dBu
(118 mV
±
1 mV)
– 23.47 dBu
(52 mV
±
1 mV)
– 15.3 dBu
(133 mV
±
1 mV)
See Figure 14 for equipment set-up and equipment settings
for steps 6 through 8.