Strange......

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Luc by way of Terry Fritz <twftesla-at-qwest-dot-net>" <ludev-at-videotron.ca>

Hi list,

This week I find an old teletype sync. motor, the motor was in
bad shape, I take it apart clean it change part of the wiring
recoated some of the winding and rebuild it. It seem to run very
well but I need to check if it was sync., because if the bearing
are to tight it will not sync. 

This motor have a fan outside of it, I put 4 pieces of white tape
( 1800 RPM motor ), the fan is black. I need a strobe to check
it; I take a dimmer-cap-ingnition coil circuit and drive a 2'
fluorescent with it. The strobe work perfectly the pattern stop
very precisely but I got 2 pattern separated by around 15 degree.

Is it the motor, It's possible if the bearing are to old and they
bited a little? Is it the dimmer circuit it's possible, in
computer simulation I made of a dimmer strangely without a good
load the pulse were not at the same place on the positive and
negative half cycle ??? Is it the fluorescent, the electrode in
it are a filament not a perfect round electrode and I know a same
electrode reacted differently to a positive or negative charge
and that could delay the discharge???

I'll need to take the scope and investigate it, this is the kind
of puzzle I really like ;-))

Cheers,

Luc Benard