Shure UC1L Service Manual page 21

Deviation Adjustment Voltage: Using a Modified SC4 IF Receiver
TRANSMITTER
AUDIO
ANTENNA
IN
OUTPUT
NOTE: DC VOLTAGES ARE
PRESENT AT MOST RF TEST
POINTS. USE A DC BLOCK
ON THE RF SIGNAL GENERATOR
TO PROTECT TEST EQUIPMENT.
SC4 IF Receiver
Output: Unbalanced
Gain: Maximum
Squelch: Mid
Tone Key switch: ON
25A1043 (RI)
ZAD–1 MIXER
R
I
ANTENNA INPUT B
L
DC BLOCK
RF SIGNAL GENERATOR
UC1 Transmitter
Power: + 9 Vdc
Gain: Minimum
Low-Pass 30 kHz: ON
High-Pass 400 Hz: ON
Figure 12. Deviation Adjustment Voltage Test Set-Up,
Steps 7 through 9, Using a Modified SC4 IF Receiver
7. Connect the UC1 rf output test cable BNC end to the input port R
(rf output) of the Zad-1 mixer.
8. Change the rf signal generator frequency to the frequency given
in Table 2, minus 10.7 MHz.
9. Turn ON the UC1 and adjust R149 until the audio volt-meter
connected to the unbalanced output of the UC4 reads the same
as the deviation reference voltage , measured above,
21
Shure UC1 Body-Pack UHF Transmitter
MODIFIED SC4 IF RECEIVER
TONE KEY SWITCH: ON
AUDIO ANALYZER
Audio Analyzer
Measurement: AC level
Output: 1 kHz
Filters: Output amplitude: + 7 dBm
AUDIO OUT
Rf Signal Generator
INT: FM
INT: 1 kHz
Modulation: See Table 2
Frequency: Oper. Freq.
minus 10.7
MHz
0.1 dB.
Service Procedures