PC Boards


I've been tinkering with various PDP-11 bits and such and found that some items were hard to locate.  One of those items is a KM11.  It originally was a two board set (one plugged into another) that was used by various PDP-11s (and other devices) for diagnostics.  These sets are nearly impossible to find.  I decided to try my hand at board design and this was the first board to attempt because it is relatively simple.  I used EagleCAD Professional as the schematic capture and board layout tool.

Here are some pictures of the first boards that I received from the board house.  I'll be stuffing them and making sure that I didn't make any gross errors.  I had the boards manufactured with gold edge fingers, green solder mask and white silk screen.  Here's a view of the component side and the solder side of the board.

I assembled two over the weekend and here's a picture of the first one.

I tested the two boards out in my 11/40.  Here's a picture of them in the 11/40 while it was running a memory diagnostic (ZMSDD0) under XXDP.



Here's a close up of the KM11s plugged into the 11/40's backplane.  Note that they are plugged into an extender.  With DEC's original design, there were two cards (one plugged into the other).  Since this board was designed to be a standard height an extender is necessary to get the KM11 out to a point where it is useful.



Unfortunately to get a clear image I had to use a flash which washed out the LEDs.  It was quite an impressive display while the memory diagnostic was running!