[GreenKeys] Teletype M12 KSR owners

[Duncan Brown]

Doug,

The basic schematic of the M12 is in Kretzman's "New RTTY Handbook", 
along with the modifications for the keyer.   If you don't have it, I 
can scan it for you.

The Museum has some extra M12 keyboards.  They are series-governed 
motors (more noise!) and are dirty, but you can have one if you need to 
replace your present unit.

Yes, i would like to see some pictures & dimensions of the cover. maybe 
we can get someone to fabricate one.

73,

Duncan



On 23-Jan-15 21:19, Doug Alderdice wrote:
> My M12, sadly, is not running.  The individual components are 
> functional, i.e. I can power up the motors on the keyboard and the 
> printer and they run and they are mechanically complete, but the 
> machine as a whole does not run.  I acquired my machine in the early 
> 90s from an older local ham when he was downsizing and he had 
> completely rewired the machine to work with a tube keyer to minimize 
> the RFI when using it on the air.  The keyer was not operating, there 
> were no schematics, etc. He had completely rewired the table to work 
> with the keyer ... and had done things like wire the power leads to 
> the printer and keyboard motors with 20 AWG wire!!
>
> I removed all of his wiring and have tried to get it back to original, 
> yet all I get on the machine are random characters.  The keyboard 
> works as I can drop it into the local loop here and can type on it 
> just fine to the other machines in the collection.
>
> I am fighting a number of variables: the condition of the contacts on 
> the table and the keyboard and printer, the contact block on the table 
> is cracked and needs to be glued or epoxied back together, and the 
> keyboard itself has been completely rewired at one time and the last 
> time I spent some time with the project I had come to the conclusion 
> that contact wiring on the keyboard doesn't match a schematic that I 
> have for the M12 keyboard.
>
> When I first got the machine I set it up on the kitchen table one 
> evening and hooked it up with every clip lead I own and managed to be 
> able to type on the keyboard and have it print on the printer. I 
> recall that I couldn't type at full speed on the keyboard and have the 
> printer follow accurately and all of the machinery made a tremendous 
> racket, as well as the electrical part of it creating a ton of RFI.  
> So I know it *should* work, but that table wiring is proving to be 
> elusive for something that should be relatively simple.  And of course 
> there is never enough time for all of the projects.
>
> I do have the cover for the machine.  I will try to get some photos 
> and measurements of it.  I believe Don needs that information as well 
> and I think I promised him that a long time ago :redface:
>
> I haven't been to the AWA museum yet.  It's been a "gee, we should do 
> that sometime" item for a local ham radio buddy and me for some time 
> now, but we haven't managed to do it.
>
> Oh, and yes, you do need a separate DC supply to run the selector 
> magnets in the printer.
>
> 73,
>
> Doug, KA2WFT


---
This email has been checked for viruses by Avast antivirus software.
http://www.avast.com