Hi Josh,

Among the pictures linked from your message about the H742a parts, there is one 
picture of you backplane.   I have been looking for some time for information 
about the following 11/45 ECO:

> KB11-00001 CODE: D May-72 [ECO]
> 
> Problem: Etch carrying +5V current from Mate-n-Lock pins to backpanel pins is 
> not heavy enough to carry required current. Correction: Run 24AWG wire in 
> parallel with etch on panels which already have Mat-n-Lock assembly 
> installed. Increase thickness of conductor with solder bead if Mate-n-Lock 
> assembly not installed. PDP-11/45 system serial number 101 and later.

The wiring arrangements at the top of your backplane look to be a bit different 
from mine, and I believe you may have this ECO implemented.  While you have 
your backplane out, could I ask that you take some closeups around the 
Mate-n-Locks along the top?  I'd be very interested to see the board traces and 
the details of the red bus wiring there.

Pictures of the toasted 11/45 suggest that the original machine had the older 
power wiring scheme (distribution panel mounted vertically on back of cabinet 
instead of horizontally at top of cabinet, etc.) although your KB11A serial 
number badge is >2000, which is curious...

Reply via email to