Sony WRT-800A, Руководство по обслуживанию

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WRT-800A (AU)
2. Frequency check
Connections
(For connecting the DC supply, refer to the “Preparations”
on page 3-3.)
Switch and control setting
S301, S302, S303, S304/ RF-87 board (A-side)
WRT-800A S301 S302 S303 S304 Channel
setting
AU66 model _ 0 1 OFF 67-01
Procedure
(1) Set the modulation analyzer as below:
MEASUREMENT : FM
MEASUREMENT RANGE : 40 kHz
HPF : 4 kHz
LPF : >20 kHz
DE EMPHASIS : OFF
(2) Set the DC output voltage of DC power supply to 1V
±
0.1 V so that battery alarm signal goes on.
(3) Check that the frequency counter (resolution : 0.1 Hz)
reading is 32.782 kHz
±
1 Hz.
(4) After the checking, remove (unsolder) the jumper wire
between TONE and GND on the AU-258 board.
3-11
RF adjusting connector
SMA-BNC
conversion connector
RF-87 Board
(B side)
AU-258 Board
(A side)
Modulation analyzer Frequency counter
RF IN AF OUT
Connect a jumper wire
between TONE land and
GND land by soldering.
(TONE signal OFF)
TONE
3-2-11. Spurious Emissions Check
Equipment and Tools
DC power supply
DC output voltage:
+
1.5
±
0.1 Vdc
DC current meter
Spectrum analyzer
RF adjusting connector (See page 3-2.)
Switch and control setting
S301, S302, S303, S304/ RF-87 board (A-side)
WRT-800A S301 S302 S303 S304 Channel
setting
AU66 model _ 0 1 OFF 67-01
Connections
(For connecting the DC power supply, refer to the “Prepa-
rations” on page 3-3.)
RF adjusting connector
SMA-BNC
conversion analyzer
Spectrum analyzer
RF-87 Board
(B side)
AU-258 Board
(A side)