Servo And Rf System Adjustment; Cap Fg Duty Adjustment (Vc-217 Board); T Reel Fg Duty Adjustment (Vc-217 Board); Pll F & Lpf F - Sony DCR-TRV8 Service Manual

3-3.

SERVO AND RF SYSTEM ADJUSTMENT

Before perform the servo and RF system adjustments, check that
the specified value of "36 MHz Origin Oscillation Adjustment" of
"CAMERA SYSTEM ADJUSTMENT" is satisfied.
Adjusting Procedure:
1. Cap FG duty adjustment
2. T-reel FG duty adjustment
3. PLL f & LPF f adjustment
0 0
4. Switching position adjustment
5. AGC center level and APC & AEQ adjustment
6. PLL f & LPF f final adjustment
0 0

1. Cap FG Duty Adjustment (VC-217 board)

Set the Cap FG signal duty cycle to 50% to establish an appropriate
capstan servo. If deviated, the uneven rotation of capstan and noise
can occur.
Measurement Point Display data of page: 3, address: 03
Measuring Instrument Adjustment remote commander
Adjustment Page C
Adjustment Address 16
Specified Value 00
Adjusting method:
1) Close the cassette compartment without inserting a cassette.
2) Select page: 0, address: 01, and set data: 01.
3) Select page: 3, address: 01, set data: 1B, and press the PAUSE
button of the adjustment remote commander.
4) Select page: 3, address: 02, and check that the data changes
starting from "1B" to "2B" to "00" in this order.
5) Select page: 3, address: 03, and check that the data is "00".
Note: If the data of page: 3, address: 03 is "01", adjustment has errors
or the mechanism deck is defective.
6) Select page: 0, address: 01, and set data: 00.

2. T reel FG Duty Adjustment (VC-217 board)

Adjust the take-up reel FG signal duty cycle to an appropriate value
so that the correct T-reel FG signal is obtained.
Measurement Point
Measuring Instrument
Adjustment Page
Adjustment Address
Specified Value
Adjusting method:
1) Close the cassette compartment without inserting a cassette.
2) Select page: 0, address: 01, and set data: 01.
3) Select page: 3, address: 01, set data: 1C, and press the PAUSE
button of the adjustment remote commander.
4) Select page: 3, address: 02, and check that the data changes
starting from "1C" to "2C" to "00" in this order.
5) Select page: 3, address: 03, and check that the data is "00".
Note: If the data of page: 3, address: 03 is "02", adjustment has errors
or the mechanism deck is defective.
6) Select page: 0, address: 01, and set data: 00.
3. PLL f & LPF f Adjustment (VC-217 board)
0 0
Mode
Measurement Point
Measuring Instrument
Adjustment Page
Adjustment Address
Specified Value
Adjusting method:
1) Select page: 0, address: 01, and set data: 01.
2) Select page: 3, address: 01, set data: 30, and press the PAUSE
button of the adjustment remote commander.
3) Select page: 3, address: 02, and check that the data changes to
"00".
4) Select page: 3, address: 03, and check that bit2, bit3 and bit 6
of the data are "0".
Note: If bit2, bit3 or bit 6 of the data is "1", there are errors. (For the
error contents, see the following table. For the bit values, refer
to "5-4. SERVICE MODE", "4-3. 3. Bit value discrimination".)
5) Select page: 0, address: 01, and set data: 00.
Bit value of page: 3,
address: 03 data
bit 4 = 1
bit 5 = 1
bit 6 = 1
bit 3 = 1
bit 2 = 1
5-41
Display data of page: 3, address: 03
Adjustment remote commander
C
17
00
VTR stop
Display data of page: 3, address: 03
Adjustment remote commander
C
1F, 20, 22, 47
Bit2, bit3 and bit6 are "0"
Error contents
PLL f , even channel is defective
0
PLL f , odd channel is defective
0
LPF f is defective
0
PLL f , final adjustment is defective
0
PLL f , final adjustment time-out
0