[GreenKeys] Model 28 Drive Voltage

[Bob Camp]

Hi

The tube is a 6005 which is an industrial version of the 6AQ5. It's 
nothing very special.

Back in the good old days I would strip this sort of stuff out before I 
did anything with a machine. I always figured it would be more trouble 
than it was worth. Now it's part of the fun.

	Enjoy!

		Bob Camp
		KB8TQ


On May 23, 2004, at 10:46 PM, jhhaynes at earthlink.net wrote:

> I knew that builtin vacuum tube keyer existed, because I have seen
> pictures of them in the parts book, but I've never seen one.  It's
> definitely not a part of most Model 28 gear.  Most of them drove
> the selector magnet with a 60ma loop directly from outside, or from
> a polar relay in the electrical service unit and the polar relay
> was operated by neutral or polar signals from outside.  Then later
> there was a transistor loop keyer.  I believe these were done mainly
> to cut down the RF noise generated by the machine.
>
> What kind of tube does it use?
>
>
>
> -- 
>
> jhhaynes at earthlink dot net
>
>