17 Jan
2014
17 Jan
'14
7:43 a.m.
From: Kyle Owen: Thursday, January 16, 2014 10:38 PM
Recently, my PDP-8/E has been acting funny. I finally
had some time tonight
to run a memory test and found that all addresses matching the pattern
XX5XX read back all zeros. Everything else tests fine. I swapped the XY
driver board (G233) and found that the problem went away.
I can't seem to locate a schematic online. My PDP-8/E preliminary
maintenance manual only describes the G227, for the 4k core board. Can
anyone help with a schematic, or judging from the symptom, point me to a
particular area on the board? I've got a 'scope and should be able to
diagnose it if I know where to start looking.
Are you looking for this?
bitsavers.org/pdf/dec/pdp8/pdp8e/MM8-EJ_Engineering_Drawings_May73.pdf
Vince