[AMRadio] Motor revisited

Bill Smith hbco2 at sbcglobal.net
Mon Apr 2 15:29:03 EDT 2007

----- Original Message ----- 
From: "Rick Brashear" <rickbras at airmail.net>
To: "'Discussion of AM Radio in the Amateur Service'"
<amradio at mailman.qth.net>

> I have been unable to find a 2 RPM Synchron motor for the timing delay on
> the old GE BT-20-A I am bringing back to life.  I can find plenty 1 RPM,
> however.  Other than taking a full minute to allow B+ to be activated
> instead of 30 seconds, I can see no reason why it wouldn't serve the same
> purpose.   I sometimes overlook the obvious, can any of you guys see
> why this would not work?
> Thanks,
> Rick/K5IZ

The manual states a delay of 30 seconds delay due to the operation of 1K1.
Perhaps the motor has been changed in the BA-10A here, but the measured
delay is 1 minute.  The motor looks original (can't read the speed without
disassembling the unit).

Never noticed the additional delay here, other than normal impatience.

If you replace the motor, make sure it has either the correct gearing or an
extended shaft.  It doesn't look like a generic motor to me.


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