RE: starting a teletype motor

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

Original poster: "Lau, Gary by way of Terry Fritz <twftesla-at-uswest-dot-net>" <Gary.Lau-at-compaq-dot-com>

When I was looking for ways to turbocharge my TTY sync motor to allow it to
spin a larger disk, I replaced the starting relay with an adjustable solid
state timer.  If the start time was too short, it would not come up to speed
and run erratically, and get quite hot in the process.  I don't think
there's a great problem with energizing the start winding for too long, as
long as you're just talking about a second or two.  Longer than that may be
a problem for the electrolytic start cap and possibly the start winding
getting hot.

So I think a manual start switch will get you running, though it's not as
nice as simply turning it on.  Perhaps a solid state delay circuit like that
on my sync RSG web page powering a relay?  BTW, I no longer advocate the
buck/boost circuit described there.
http://people.ne.mediaone-dot-net/lau/tesla/tesla.htm

Gary Lau
Waltham, MA USA


Original poster: "by way of Terry Fritz <twftesla-at-uswest-dot-net>"
<CTCDW-at-aol-dot-com>

Hello all!

I posted a wekk ago about finding a starting relay for my teletype motor. 
They must be hard to come by, so I was wondering if the motor sould be 
started via 2switches, one acting as a start relay and switched manually. 
Obviously this COULD be done, but my real question is: would the motor have 
to come up to full speed (synchronized) before disengaging the start
winding? 
and what might happen if it was in start mode for too long, or not long 
enough? although I'm not sure if it is started in the same way, Hammond 
organs had a "start" and "run" switch to start their sync motors. You simply

held the start switch on for a short time, and then hit the run switch. Any 
info would be appreciated

Chris W