[GreenKeys] Teletype Model 15 power Q's...

[Eric & Jia Bigham]

Hmmm, just did some resistance measurements ;o … the DC terminals measure 810 ohms with the test nob in both positions and the jack line measures about 100 ohms the same ;o .  Could the test nob have been bypassed somewhere ;o ?  There is that rewiring in the back - wires that I can’t immediately find on the diagram ;o .  Would trying to apply a low voltage to the DC terminals, just to see if there is a response somewhere, be a bad idea ;o ???  :)


> On Nov 10, 2016, at 4:21 pm, Jim Haynes <jhhaynes at earthlink.net> wrote:
> 
> And when the line-test knob is pushed in, if you measure on the cord
> with the phone plug, you'll probably see a fairly low resistance, which
> is the selector coils alone.  If you see an open circuit, well you'll
> have to do some tracing to see what is wrong.  The circuit should lead
> through the selector coils, through the keyboard contacts and through
> the line-test switch and the send-receive-break switch.  With the
> line test knob pulled out you'll probably see a low resistance across
> the phone plug.
>