Sony WRT-822B, Service Manual

Page: 19 / 46

3-11
WRT-822B
2. Frequency check
Connections
(For connecting the DC power supply, refer to the “Preparations”
on page 3-3.)
Procedure
n
Perform the checking with the Mic input connector (SMC9-
4P) short-circuit.
(1) Set the modulation analyzer as follows:
MEASUREMENT: FM
MEASUREMENT RANGE:
±
40 kHz
HPF: 4 kHz
LPF: >20 kHz
DE EMPHASIS: OFF
(2) Check that the frequency counter (resolution : 0.1 Hz
setting) reading is 32.768 kHz
±
1 Hz.
3-2-10. Battery Alarm Signal Check
Equipment and Tools
DC power supply
DC output Voltage:
+
3.0
±
0.1 V dc
DC ammeter
Frequency counter
Spectrum analyzer
Modulation analyzer
MM-SMA (J) connector (Part No. J-6402-480-A)
SMA-BNC (J) connector (Part No. J-6402-490-A)
Switch and Control Setting
The following setting is to be perform with the SET switch
(S402) , “
+
” switch (S400) and “
_
” switch(S401).
Transmitting Channel setting:
CE21 model; Group 00, 21-01 channel (470.125 MHz)
CE33 model; Group 00, 33-01 channel (566.125 MHz)
CE62 model; Group 00, 62-01 channel (798.125 MHz)
CE67 model; Group 00, 67-01 channel (838.125 MHz)
U14 model; 14-01 channel (470.125 MHz)
U30 model; 30-01 channel (566.125 MHz)
U62 model; 62-01 channel (758.125 MHz)
U66 model; 66-01 channel (782.125 MHz)
Attenuation setting: 0 dB
Accumulated time setting: “Don't Care”
1. Frequency deviation check
Connections
(For connecting the DC power supply, refer to the “Preparations”
on page 3-2.)
MB-940 Board
(A side)
Modulation
analyzer
Frequency counter
RF IN
AF OUT
MM-SMA (J)connector with SMA-BNC (J) connector
CN301
MB-940 Board
(A side)
Spectrum analyzer
CN301
TP501 (GND)
Connect a jumper wire between
TP200 and TP501 (GND) by soldering.
(TONE signal : OFF).
TP200
MM-SMA (J)connector with SMA-BNC (J) connector
Jumper
wire