[GreenKeys] Fw: New Introduction

[Sam Hallas]

Nico de Jong wrote:
>  For the danish data museum, I'm presently trying to revive a
>  teleprinter called GNT, type 15. It has built-in puncher and tape
>  reader. It seems to come from the danish telex network, as it has
>  been type approved by the PTT. My guess is that the connections are
>  identical to Siemens, as there are 8 cables with the same colors as
>  used by Siemens. Furthermore, I can measure about 200 ohm across 2
>  combinations. What I cannot guess, is whether it is a 20 or 40 mA
>  machine. Siemens uses 40. What could happen if I press 40 mA through
>  a 20 mA machine ?

Nico,
Hello there from the UK.

I didn't know that GNT made any printer equipment. I have seen 
advertisements for their Morse equipment in old magazines - undulators, 
reperforators etc. Is it conceivable that you have a re-badged Lorenz 
LO15? Here's a picture of one in the RAF Signals Museum up the road from me.
http://homepage.ntlworld.com/s.hallas/greenkeys/21_Lorenz_LO15.jpg

On the current question: Is there a series resistor for local copy? If 
it's 2k then the magnet is 40 mA. 4k and its 20 mA. I think that if you 
underrun a 40 mA magnet the print will be unreliable and possibly 
erratic. Best to try that way round rather than to burn out the magnets!

Henning Treumann, DF30E, may be able to answer your questions if he's 
reading.

Cheers,
Sam Hallas