[GreenKeys] model 14 ktr

[epvgk at limpoc.com]

On Sun, Oct 16, 2011 at 10:51:53AM -0700, John Nagle wrote:
> 
>    If you're that far along, you should be able to get perfect
> operation.  98% accuracy is sub-par.  Local operation should
> be above 99.99% accuracy.


Ok, I've sorted out some of the problems. The 14 KTR keyboard sends perfectly
now. After digging into it, I discovered that one of the lockout arms that 
engage the keyboard contacts was sort of glued in place by old congealed oil.
Once it was freed up, cleaned, and re-oiled, it sends perfectly now, at least
as received by a model 28 and a computer uart. 

The other issue is that the unit appears to have some odd sort of home-made
selector magnet which has a huge DC series resistance of around 2k, and seems
happiest at 20mA rather than 60mA. Even then it is pretty dubious though and
I feel like the best course of action would be to replace it with  a real 60mA 
holding-type selector magnet assembly, which I believe George might be 
planning to dig out for me anyway.  Still, with the loop current tweaked 
just right, it's able to copy its own output better. 


eric