Navaid Devices AP-1, Руководство пользователя

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- A.4 -
APPENDIX B
GYRO NULL ADJUSTMENT
If you accidentally turned the GYRO NULL trimpot, it will have to be adjusted. You will
need a battery operated digital voltmeter. Do not use an AC powered meter unless it has
the ability to measure a floating differential voltage.
Adjusting the GYRO NULL trimpot is easy; you just turn the trimpot until you voltmeter
reads zero. There are two precautions:
1) You have to insure that the AP-1 is held stationary during the procedure since the
slightest movement will affect the voltmeter reading.
2) The cover must be on the AP-1 because the gyro is sensitive to light.
Set your voltmeter to its most sensitive DC scale. Put the AP-l's MODE SWITCH in the
center position. Put either voltmeter lead on pin 11 of the AP-l's rear connector (see Fig.
3 on page 7). The other lead goes on pin 10.
Apply power to the autopilot and adjust the GYRO NULL trimpot until the meter seems
to average a zero reading. Even with the AP-1 held rock steady, it is normal for the
reading to bounce around several tens of millivolts, so don't expect to get a perfect
reading of zero, especially if you have a very sensitive meter.
If you cannot obtain a zero reading, there may be a problem with the autopilot. Call for
assistance.