[GreenKeys] Where's the clankity, clank, clank?

[John Lawson]

On Tue, 16 Oct 2007, Reggie Moody wrote:

> Use to own a model 15 and fed signals to it with a Hal 6000.  Sold both 
> and regretted it years later.  Now have a model 15, but when I plug it 
> in, the motor runs but no out of control "clankity, clank, clank." Where 
> do I start checking?


   Your HAL supplied "loop current" to the selector magnets in the Mod 
15...  in the absense of that current (nominally 120VDC at 60 mA) the 
machine will "run open"....   if it's just a stand-alone Mod 15, you will 
need to supply it with loop current from somewhere... then the Terminal 
Unit, the "TU" or whatever you will be using to decode the audio signals 
from your reciever or computer, will turn those tones into on/off 
switching of the loop supply, causing the selector magnets in the MOd 15 
to properly operate and make the machine print what is coming down the 
line to it.

   If your MOd 15 has what seems to be a power supply attached, look for a 
switch that says something like "Local / Line", etc.


   At any rate, as it is, your 15 is wanting you to give it it's Loop 
Current supply.

  Go to www.rtty.com and check out the various interface units for 
attaching a mechanical teletype to a computer port.

   Cheers

John KB6SCO