Mhz Crystal Oscillator Adjustment (Vc-188 Board) - Sony Handycam CCD-TR86 Service Manual

6. 28MHz crystal oscillator adjustment
(VC-188 board)
Purpose :
Adjusts 28MHz crystal controlled oscillation
for synchronizing clock.
Adjustment error : Loss of synchronization or loss of color.
Subject Not required
IC201 %¢ pin
Measurement Point
Measuring Instrument Frequency counter
Adjustment Page F
Adjustment Address 3D
Specification 4433618.75 ± 17Hz (PAL)
3579545 ± 17Hz (NTSC)
Adjustment procedure:
Order Page Address
1 6 00
2 F 3D
3 F 3D
4 6 00
Reference: Conversion between the hexadecimal
number and decimal number.
In some adjustment items, data appears in hexadecimal numbers on
the DDS display or on the adjustment remote commander.
Maintenance engineers are expected to convert the displayed
hexadecimal numbers to the corresponding decimal numbers using
Data
01 After setting the data, press the PAUSE button. (Preparation)
Change the data using PLAY, STOP buttons until the frequency satisfies the specification.
Press the PAUSE button.
00 After setting the data, press the PAUSE button. (End)
Procedure
the following conversion table.
Make a required calculation described in each adjustment item. Then
re-convert the result of calculation back from the decimal numbers
to the corresponding hexadecimal numbers using the following
conversion table.
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