[GreenKeys] Model 15 KSR

[Ralph Mowery]

There were two kinds of selector magnets in use.  One was a holding and
I think the other kind was a pulling magnet, not sure of the name.
Without running out to check I want to say the pulling type had a
spring  connected to the moving part and was opposit the magnets and the
holding magnet does not have the spring among other differances. They
both can be put in series for 20 ma or parallel for the 60 ma loop.  You
do not need a polor relay to use the Model 15 or 19 equipment.  The most
common way was to use around 150 volts and put a series resistor of
around 2000 to 3000 ohms in the circuit and adjust it with the keying
device (tuve or transistor) for  the current the magnets are wired for.


Jeff Seidel wrote:
> 
> Hello all,
> 
> Im looking for some information on a Model 15KSR  I just picked up today.
> 
> I first noticed the unit does not have a polar relay unit on it and also I see the
> selector and magnets look quite different than the ones on my Model 19 set.  There
> is also no Line/Test switch on it.
> 
> Were there Model 15's with older style selectors and did they use them without the
> polar relays?  Being a novice at this I only know what Ive seen on my Model 19
> set.
> 
>