SERVICE MANUAL
5–22
10FEB97 – SM3226-1
Clock Frequency for Electromagnetic Pump
Use this procedure to check the vacuum pressure and the clock frequency for the ELECTROMAGNETIC PUMP
when the film suction is malfunctioning.
Caution
Close the MAGAZINE WINDOWS or remove the
MAGAZINES before doing this adjustment.
To Check:
[1] De-energize the LASER PRINTER.
[2] Remove the BACK IMAGE UNIT COVER. If
necessary, see the procedure on Page 2–3.
[3] Open the SEQUENCE BOARD SHIELD.
[4] Connect a 10X Probe TL-2074 to the Channel A input of the Oscilloscope TL-3348.
[5] Set the Volts/Div. to 2.0 V.
[6] Set the Sec/Div. to 5 msec.
[7] Connect the GROUND CLIP of the OSCILLOSCOPE PROBE in Channel A to CPG5 on the DRIVER
BOARD.
[8] Connect the 10X OSCILLOSCOPE PROBE in Channel A to CPCK on the DRIVER BOARD.
[9] Energize the LASER PRINTER.
[10] Observe the waveform on the OSCILLOSCOPE. The clock frequency should be 55
±
3 Hz. One cycle should
be between 17 ms and 19 ms.
To Adjust:
[11] Rotate POTENTIOMETER VR6 until the wave cycle is within specification.
H129_0601AC
SHIELD
BOARD
SEQUENCE
H129_0601ACA
