Re: am I a SRSG failure?

["Jim Lux" <jimlux-at-jpl.nasa.gov> (by way of Terry Fritz <twftesla-at-uswest-dot-net>)]

For a low buck sync checker (phasing isn't adjustable, and performance is
pretty wretched, but it's cheap) a neon bulb running of the AC line with a
series resistor makes a dandy strobe to see if you are really synced.  LED
and AC source also works (flashing at 60 Hz)...  At least it's better than
the fluorescent lights.

The only real problem is that both of these are pretty darn dim, so you have
to have that motor running in the dark....

And of course, Terry has a design for a modified radio shack strobe that
would work much better in room lights (or at least in dim light and not
total darkness, like the neon bulb or LED needs).

-----Original Message-----
From: Tesla list <tesla-at-pupman-dot-com>
To: tesla-at-pupman-dot-com <tesla-at-pupman-dot-com>
Date: Wednesday, August 09, 2000 6:51 PM
Subject: Re: am I a SRSG failure?


>Original poster: Terry Fritz <twftesla-at-uswest-dot-net>
>
>Hi Dave,
>
>        Don't worry, I simply HAS to work, unless the laws of physics are
not
>enforced in your neighborhood :-))
>
>First, be sure the motor shaft turns freely and nothing is binding.
>
>What is the diameter of the rotor, horse power, and how wide are the two
>flats?  I don't know the best dimensions for 3600RPM but someone will...
>
>Count the number of poles in the motor.  These are the steel projections
from
>the frame or stator that are close to the rotor.  That will help us
determine
>the flat size.
>
>There may be something wrong with the florescent lights (no!, I'm serious!
>;-)).  Today they use electronic ballasts and other goofy things (like long
>persistence) that may be messing that test up...
>
>Be sure there are good light and dark areas on the shaft or make a strobe
disk
>to put on the shaft.  Florescent lights give a pretty fuzzy indication so
you
>need good black and white marks to show well.
>
>Your too close to fail now!  I have heard of milling machines "eating" the
>rotor up and other obvious disasters, but your motor simply must work...
>
>Cheers,
>
>        Terry
>
>
>
>At 09:05 PM 8/9/00 -0400, you wrote:
>>
>> Hi everyone,
>> I recently milled two flats into my 2 pole 3450RPM motor withsome files
and a
>> barrel sander and drill (oww, my arms) to make it salient, however when I
did
>> the flourescent test, the motor appeared to be lagging behind what it
should
>> be in rpm's.  It doesn't search either, it only runs as it seemed to have
ran
>> before I ever modified it.
>>     What's wrong?  I made sure to make the flats the same width as the
"dead
>> poles" (which are the width of 3 poles right?)  And they are not off the
180
>> degree marks either.  I just don't see what is wrong with the flats as
far as
>> the examples I used of other modified motors.  Possibly I should mill the
>> flats more?
>>
>> Dave
>
>
>
>
>