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EICo 666 Calibration

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EICo 666 Calibration Empty EICo 666 Calibration

Post by tcicero Mon May 23, 2011 12:47 pm

My Eico 666 won't calibrate properly. I think I need to replace the 2 -100K pots any advice. Where do I purchase the pots?

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EICo 666 Calibration Empty Re: EICo 666 Calibration

Post by librarycustodian Sat Jun 18, 2011 8:25 pm

Hi: Resistors R8 and R19 are frequently far out of tolerance and are in series with the calibration pots R7 and R18, so they may be the problem. If the problem does turn out to be the pots, unsolder and remove from the chassis. Carefully bend the tabs and disassemble the pots for a thorough cleaning.

Rectifier CR1 and capacitor C1 are also in the calibration circuit, so check or replace if other steps fail. Of course, faulty switch contacts will cause erratic calibration, too.

I have a set a Eico schematics upon which I have traced the calibration, leakage test, merit test, line adjust, gas tube test,etc.

If anyone would like a set of the tracings, send me an E-mail at (change "at" to "@" of course).

The charts are also available at this web site:

Good luck,

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