Shure UC2, Руководство по обслуживанию

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Shure UC2 Hand-Held UHF Transmitter
Service Procedures 15 25A1044 (RI)
Frequency
Use this service procedure to correctly align the transmitter’s
operating (output) frequency. C510 tunes the voltage-controlled
oscillator (VCO) to the operating frequency selected, with a 1 – 4 Vdc
tuning range.
C314 adjusts the reference oscillator on the synthesizer, U304.
FREQUENCY COUNTER
DC VOLTMETER
+
–
CH 2
CH 1
TP30
C510
U501
C314
J2*
RF
GND
S302
RED
S301
GREEN
TPRF1
*R40 and J2 are placed for JA, JB frequencies only.
RF GND: FEED THRU
HOLE ON PCB
R40*
UC2 Transmitter Frequency Counter
DC Voltmeter
Power: ON (+9 Vdc) Operating freq: See Table 2 C : TP30
Operating freq: See Table 2 Connect CH 2: TPRF1 and GND Connect – : RF GND
Channel switch: See Table 2 For JA,JB frequencies:
Connect to J2
Group switch: See Table 2
Connect to J2
(pcb rf side 1)
Figure 7. UC2 Frequency Test Set-Up
1. Put a dc voltmeter across TP30 (tuning voltage line) and
RF GND
.
2. Adjust the
VCO
trimmer, C510, until the voltmeter reading
matches the appropriate entry in Table 2,
±
0.125 Vdc.
3. Adjust the variable capacitor, C314, until the frequency counter
measurement matches the appropriate frequency in Table 2,
±
1 kHz.
4. Leave the test cable connected to the rf output.
5. Turn the transmitter OFF.
6. The dc voltmeter can be removed from TP30.