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Full Version: Adjusting card reader eccentric screw
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I would like to try the adjustment method based on motor current draw as described in the Service manual. Since my calculator is in pieces can I disconnect the motor leads and use a 1.5v(?) battery in the test?

Thats how I do it and I have yet to have a problem.

Cheers, Geoff

Just to be sure, is the motor test voltage supposed to be 1.5 volts? I recall having seen that somewhere but now can't find it.

The spec says I should adjust the eccentric screw to get 180 +/- 20 mA while holding the card from going through. The lowest I can get is about 330 mA. When the motor is running freely w/o card it draws about 190-205 mA. This is while using a nominal 1.5 volt battery, which actually is about 1.4 volts, with a digital multimeter in series.

I am using O-rings bought from the eBay seller.

Is this typical?

Edited: 17 Mar 2010, 4:35 p.m.