Pll Capture Range Adjustment (Rp-228 Board); Ic774 41.85 Mhz Vco Check (Rp-228 Board) - Sony DSR-20MD Service Manual

6. PLL Capture Range Adjustment (RP-228 Board)

Mode Recording/Playback
Signal Color bar
CH1: Pin qk of CN775 (C1ERP)
Measurement Point
CH2: Pin 6 of CN775 (JSWP)
Oscilloscope
Measuring Instrument
Trigger source: CH2
Adjustment Page C
Adjustment Address 46
Adjusting method:
1) Record color bar signal for two minutes on any tape.
2) Select page: 0, address: 01, and set data: 01.
3) Write the following data in page: C, addresses: 4B and 5A.
To write the data, press the PAUSE button of the adjusting
remote commander each time data is set.
Page: C, address: 4B, data: 80
Page: C, address: 5A, data: 00
4) Playback the part recorded with the color bar signal.
5) Select page: C, address: 46, set data: 80, and press the PAUSE
button of the adjusting remote commander.
6) Select page: C, address: 46, set the data to "60", and check
that the pulse is not set at the audio area head of the ERRP
waveform's ODDch of the oscilloscope (CH1).
7) Select page: C, address: 46, set the data to "A0", and check
that the pulse is not set at the audio area head of the C1ERP
waveform's ODDch of the oscilloscope (CH1).
After confirming steps 6) and 7), select page: C, address: 46,
set data: 80 again and proceed to step 12).
8) If the pulse is set in steps 6) and 7), select page: C, address:
46, increase the data from "80", and read the data D
pulse is set at the audio area head of CH1.
9) Select page: C, address: 46, decrease the data from "80", and
read the data D when the pulse is set at the audio area head of
2
CH1.
10) Obtain the average value of D
11) Select page: C, address: 46, set data: D
button of the adjusting remote commander.
12) Select page: C, address: 4B, set data: 00, and press the PAUSE
button of the adjusting remote commander.
13) Select page: C, address: 5A, set data: 8C, and press the PAUSE
button of the adjusting remote commander.
14) Select page: 0, address: 01, and set data: 00.
When the pulse is not set at the audio area head.
CH1
CH2
When the pulse is set at the audio area head.
CH1
CH2
ODD ch
3.33 msec
Fig. 5-3-8.
when the
1
and D , and take it as D .
1 2 3
, and press the PAUSE
3

7. IC774 41.85 MHz VCO Check (RP-228 Board)

Mode
Signal
Measurement Point
Measuring Instrument
Adjustment Value
Checking method:
1) Select page: 3, address: 39, and check that the displayed data
is "37" to "C9".
5-70
E-E
Arbitrary
Page: 3, address: 39 on displayed data of
adjusting remote commander
"37" to "C9" (0.6 to 2.2 Vdc)