Ricoh C211 Service Manual page 184

9.13 INK DETECTION ADJUSTMENT
CH1
1~
(Standard Signal)
II
mm
4 psec ~0"5psec
~
CH2
J
i! I
(Detection Signal)
.
[Ar
TP1
TP2 -
%$-
@
0
TP~12 '"
-[B]
— .—. .
Purpose: To ensure correct detection of a no ink condition when all the ink has
1.
2.
3.
4,
5.
been consumed.
Remove the rear cover of the machine.
Position SW901 [A] on the ink detecting board to the oil type (upper) position.
Connect the CHI probe of an oscillosmpe to TPI, the CH2 probe to TP2
and the G ND lead to TP-I 2V, Select the 5 microsecond range,
Install a drum with no ink or remove the ink cartridge and make prints until
the Add Ink is displayed (the ink detecting pin is not in contact with the ink).
Make sure that the waveform is as shown above when the ink detecting pin
is not in contact with the ink.
c This adjustment should be made under normal conditions (20"C/65% RH).
NOTE: The period of the waveform varies inversely with temperature.
(High temp. ~ reduced period. Low temp. + increased period)
6. If incorrect, adjust the ON timing of the detection signal using VR901 [B] on
the ink detecting board.
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