Re: [TUHS] PDP 11/34a Serial Communications Problem - TUHS

6 Feb 2017

...
  From: Mark Hare &lt;markhare(a)buffalo.edu&gt; 
...
  I believe I have found the problem. 
Excellent!

...
  Looking at the DL11-W, I saw that there is an
uncovered trace on the
 circuit board just below the pins of the BERG connector.  It appears
 that the exposed conductor ends of the cable were making contact with
 this trace, which shorted the entire cable together. 
Shorting any set of DL11-W pins together still shouldn't have caused that
symptom, AFAICS.

I'm too lazy to pull out a DL11-W, and prints thereof, to check, but I suspect
that what actually happened is that trace carries some 'interesting' signal,
and it got grounded 'or something' by the exposed ends of the flat cable.

...
  I'm just glad that there doesn't appear to
be any lasting damage. 
Indeed! I was worried about that...

	 Noel