Sony DVCAM DSR-250 Service Manual page 40

2-4-6. FWD/RVS BACK TENSION CHECK AND ADJUSTMENT
1. Preparation before check
Mount the mechanism deck in the main unit, connect all the
connectors, then insert the mini DV torque cassette (J-18) into the
mechanism block.
[FWD side]
9.5 ± 1.5 × 10
-1
mN • m
2-4-7. PREPARATION FOR ADJUSTMENT AND TAPE PATH CHECK
Preparation before adjustment (connection and setting)
1. Mount the mechanism deck in the main unit.
(Connect all the connectors.)
2. Clean the tape running side.
(Refer to Section 2, "Periodic check".)
3. Connect the adjustment remote commander (J-5) to the LANC
jack.
Adjustment remote commander
(RM-95)
4. Turn the HOLD switch of the adjustment remote commander
to the ON position.
5. Select page: 3, address: 33 and set data: 08.
6. Select page: 3, address: 26 and set data: 31.
7. Connect an oscilloscope to VI-156 board CN007 via the CPC-
13 jig (J-6082-388-A)(J-8).
Channel 7: VI-156 board, CN007 Pin 2 (Note)
External trigger: VI-156 board, CN007 Pin 3
Note: Connect a 75 Ω resistor between pins 2 of CN007 and 1 (GND).
75 Ω resistor (Parts code: 1-247-804-11)
Mini DV torque
cassette (J-18)
Visually check the gauge
block of the cassette with the
cabinet (L) assembly removed.
[RVS side]
9.5 ± 1.5 × 10
-1
mN • m
2. Check and adjustment
• FWD (TG2) side
The torque value should satisfy 9.5 ± 1.5 × 10
the mini DV torque cassette runs in the FWD mode. If it does
not satisfy this, take the following measure.
Re-attach the spring to the upper hook if the
measurement value is beyond the specifications
or re-attach the spring to the lower hook if the
measurement value is below the specifications.
Then, repeat the measurement.
• RVS (TG7) side
The torque value should satisfy 9.5 ± 1.5 × 10
the mini DV torque cassette runs in the RVS mode. If it does
not satisfy this, take the following measure.
Re-attach the spring to the upper hook if the
measurement value is beyond the specifications
or re-attach the spring to the lower hook if the
measurement value is below the specifications.
Then, repeat the measurement.
Be careful that these spring blocks may hinder
the FL motor.
For more details,
refer to page 5-52.
Tape path check (checking the RF waveform)
Play back the tracking tape (J-17) and check the states at the entrance
and exit of the RF waveform. If it is not flat at either side, perform
the adjustments from Adjustment Start-4 in the flowchart on page
5-52.
5-56
-1
mN • m while
For more details,
refer to page 5-52.
-1
mN • m while
Normal entrance and exit sides
Faulty entrance side
Faulty exit side