[GreenKeys] Tuning Fork

[wa2hwj at att.net]

ZCZC

Tuning forks with the "shutters" were used to set the speed of governed
motors. Tuning forks used as audio references (or in AFSK oscillators)
were your common music store variety. I believe the 440 HZ tone
is musical note "A" and those forks were modified to oscillate at
425 HZ by filing the "crotch". ( a little side trivia...440 HZ and 350 HZ
together give you "dial tone")

I have a couple of 14/15 vintage TTY's that have goverened motors and must
admit that I've never had to touch them as far as motor
speed. They do generate some RF hash when running. I had a
Model 28 with a LMU-10 governed motor and it was
well shielded for RF and ran fine. The Gov't actually had a
modified 28RO that used the LMU-10 as a variable-speed
shifter.

Jack WA2HWJ

NNNN

-------------- Original message from "Larry Tighe" <larryradio at worldnet.att.net>: -------------- 


> Don and the Greenies, 
> 
> Had to share Leanne's answer with you re: governed motors :>) One of those 
> rare moments when I laugh out loud at the monitor screen....Lar 
> 
> ----------------------------------------- 
> 
> Larry, I wouldn't wish one on my friends, only to my worst enemy 
> 
> Leanne 
> 
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