AV-21F9
ADJUSTMENTS
B1 POWER SUPPLY
Measuring
Item Test point Adjustment partDescription
instrument
Check ofSignalTP-91 (B1)1. Receive a whole black signal.
B1 POWERGeneratorTP-E """""()2. Connect a DC voltmeter between TP-91 (B1) and ") TP-E (
SUPPLY[S1(between pins 1 and 5 of the connector S1).
DC Voltmeter connector]3. Make sure that the voltage is DC113.3 ? 1.5V.
FOCUS ADJUSTMENT
Measuring
Item Test point Adjustment partDescription
instrument
Adjustment SignalFOCUS VR1. Receive a cross-hatch signal.
of FOCUSgenerator[In HVT]2. While watching the screen, adjust the FOCUS VR to make the
vertical and horizontal lines as fine and sharp as possible.
3. Make sure that, when the screen is darkened, the lines remain
in good focus.
IF CIRCUIT ADJUSTMENT
Measuring
Item Test point Adjustment partDescription
instrument
Adjustment RemoteVCO (CW)l Under normal conditions, no adjustment is required.
of VCO (CW) control unitTRANSF.1. Select 1. IF from the SERVICE MENU.
[On IF PWB]2. Press the 1 key to select 1. VCO.
3. Select a receivable broadcast channel with the CHANNEL key.
4. Turn the core of VCO(CW) TRANSF. until the colour of the
characters "TOO HIGH" displayed on the screen changes from
VCO (CW) ]]].]] MHzfv
blue to yellow. (Step 1)
5. Then slowly turn the core of VCO(CW) TRANSF. counterclock-
TOO HIGH
ABOVE REFERENCEwise until the characters "ABOVE REFERENCE" changes from
BELOW REFERENCEYELLOWblue to yellow. (Step 2)
TOO LOW
6. Further slowly turn the core of VCO(CW) TRANSF. until the
DISP : EXITcolour of the characters "BELOW REFERENCE" changes from
blue to yellow. (Step 3)
7. Press the DISPLAY key three times to return to normal screen.
8. Perform CHANNEL PRESET again, and make sure that each
broadcast is being received properly.
Step
Screen display
123
TOO HIGHYellowBlueBlue
ABOVE REFERENCEBlueYellowBlue
BELOW REFERENCEBlueBlueYellow
TOO LOWBlueBlue
No. 5603714 |