Toshiba DP1200, Service Manual

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3) Make a copy.
Check the adjustment level (shown in the above table) of the ex-
posure test chart (Gray Scale).
(When too bright): Decrease the value displayed on the copy
quantity display.
(When too dark): Increase the value displayed on the copy quantity
display.
* The value can be set in the range of 1 – 99.
3. High voltage adjustment
A. Main charger (Grid bias)
Note:
Use a digital multi meter with internal resistance of 10M or
more measurement.
After adjusting the grid LOW output, adjust the HIGH output.
Do not reverse the sequence.
Procedures
1. Set the digital multi meter range to DC700V.
2. Set the positive side of the test rod to the connector CN11-3 (GRID)
of high voltage section of the power PWB and set the negative side
to the frame ground (radiating plate).
3. Execute SIM 8-3. (The main charger output is supplied for 30 sec
in the grid voltage LOW output mode.)
4. Adjust the control volume (VR-141) so that the output voltage is
400 – ± 20V.
5. Execute SIM 8-2. (The main charger output is supplied for 30 sec
in the grid voltage HIGH output mode.)
6. Adjust the control volume (VR-142) so that the output voltage is 580
±10V.
B. DV bias adjustment
Note:
A digital multi meter with internal resistance of 1G must be
used for correct adjustment.
Procedures
1. Set the digital multi meter range to DC500V.
2. Set the positive side of the test rod to the connector CN-10-1 (DV
BIAS) and set the negative side to the connector CN10-2 (FG).
3. Execute SIM 8-1. (The developing bias is outputted for 30 sec.)
4. Adjust the control volume (VR-121) so that the output voltage is
– 400 ± 5V.
DP1200/1500
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