[GreenKeys] Free Main Shaft and Motor

[John Nagle]

> From: "Larry Tighe" <larryradio at att.net>
> Subject: Re: [GreenKeys] Free Main Shaft and Motor
> To: "Derek Cohn/WB0TUA" <vibroplex at mindspring.com>,	
> 
> http://www.railroadmorse.com/tty%20003.jpg
> 
> I don't think this is a tty motor...I think it was a fly spot scanner used 
> in the first tv picture transmissions  LOL
> 
> lar 

     No, that disk is just a homebrew tachometer with an LED/photodiode
detector.  It's a governed (non-synchronous) motor; the lever next
to the encoder wheel is for adjusting the governor.  The stock
adjustment procedure involves a flywheel with black and white stripes,
and a tuning fork with fins that open and close through which the
stripes are viewed.  This looks like a mod someone might have made
in the 1970s.

    A flying spot scanner usually uses a Nipkow disk, with a spiral of holes.
There are several in the Henry Ford Museum, in Dearborn, MI.

					John Nagle