7156 Owner’s Guide
Chapter 4: Diagnostics
September 1997
41
Caution:
Do not adjust the potentiometers if the green LED is not lit (indicating the
switches are incorrectly set). Doing so causes an incorrect noise sample.
Note:
You may need to perform the following steps several times to get the
potentiometers adjusted for the least amount of noise.
Note:
The operator panel may differ depending on the model. To put the printer on- or
off-line, use a paper clip or other pointed object to depress the plunger (in place of the On
Line button) on models with that item.
1. Remove the front cover from the hinge arm assembly.
This will make it easier to perform the adjustment.
a. Open the hinge arm assembly.
b. Remove the screws holding the front cover to the hinge arm assembly.
c. Unsnap the front cover from the hinge arm assembly.
d. Close the hinge arm assembly to finish the adjustment.
2. Insert a blank slip into the slip station from the left side so that it covers the MICR read
head, but does not come into contact with the feed rolls.
Be sure that the slip covers the MICR read head and stays in position.
3. Set both potentiometers (on the PC board) to mid range using a screwdriver.
4. Adjust the lower potentiometer (R9) on the PC board either direction.
The green LED should be on before you adjust the potentiometer.
5. Press the Paper Feed button on the PC board to take a noise sample.
Repeat steps 4 and 5 until the lowest number of characters is printed. You may need to
adjust the potentiometer both directions to get the best setting.
If “OK” is printed on the receipt, go to number 8.
6. Adjust the upper potentiometer (R8) on the PC board either direction.
The green LED should be on before you adjust the potentiometer.
7. Press the Paper Feed button on the PC board to take a noise sample.
Repeat steps 6 and 7 until the lowest number of characters is printed. Adjust the
potentiometer both directions to get the best setting. When “OK” is printed, the noise
is low enough for the MICR to operate successfully.
8. Press the On Line button (or plunger) to put the printer off-line.
9. Set the DIP switches back to the settings for normal operation (on-line mode).
See “Switch Settings” in “Chapter 5: Communication” for the settings.
10. Reattach and close the front cover if it was removed.
11. Press the On Line button (or plunger) to put the printer on-line.
The green LED flashes when the printer cycles. The settings are entered into EEROM.
Summary of Contents for 7156
Page 6: ...Contents 7156 Owner s Guide September 1997 iv...
Page 38: ...Chapter 3 Solving Problems 7156 Owner s Guide September 1997 32...
Page 118: ...Chapter 6 Commands 7156 Owner s Guide September 1997 112...
Page 122: ...Appendix A Specifications 7156 Owner s Guide September 1997 116...
Page 129: ...7156 Owner s Guide Appendix B Print Characteristics September 1997 123...
Page 130: ...Appendix B Print Characteristics 7156 Owner s Guide September 1997 124...