(ET) E20 problem in forward, quickly resolved.

[Christopher Zach <cz alembic crystel com>]

So my E20 was mowing away today, and suddenly I lost all speeds other 
than 1 in forward. No problem in reverse. Wait a few minutes, everything 
goes back to normal.

Odd.

I sat down to take a look at it and figured the problem was in card 4. 
Replaced the two field diodes since one of them (upgraded years ago) 
looked a bit burnt. Still same problem. Issue was not field, but power 
to 1a,2a,3a coils.

Which goes from the armature through CR402 or CR403 on card 4. CR402 was 
the most likely culprit, but diode looked fine. Checked voltage, only 9 
volts on either side of the diode. Odd.

Checked the connector next. Sure enough one of the two fingers had 
broken off, and the other finger was not making proper contact. Bent the 
other connector slighty, cleaned up the pads on card 4, put it in, all 
is now well again.

So there you go. If you lose speeds 2 and up in one direction but not 
the other check around CR402.

C