Ricoh FACSIMILE FAX77, Field Service Manual

Page: 123 / 197

Step Item
Procedure
6 Scan line 1. Access the SBU as explained in
“Preparation” above.
2. Set the oscilloscope scale to 0.2
V/unit (vertical) and 0.5 ms/unit
(horizontal).
3. Connect the oscilloscope probe to
XVIDEO (pin 1 - blue wire) and the
ground to GND (pin 4 - black wire)
on the test lead.
4. Light the xenon lamp (see page 2-
24).
5. Place the scan line test chart [A] on
the exposure glass as shown.
6. Loosen the SBU securing screws
(see procedure 1).
7. Adjust the waveform with the adjust-
ing knobs until the waveform is as
shown on the right.
3-18