[TUHS] flaky webster or sigma WQESD4 and RQD11 controllers on KA650???

Robertdkeys at aol.com Robertdkeys at aol.com
Sat Dec 14 14:00:39 AEST 2002

The particular webster wqesd4 I have looks like
about an '86 or so board, from chip dates, and
the main chip that is socketed is marked with
"ENGR-SAMPLE"...doh....  Maybe I do have a very
early board that won't run with a faster cpu.
The rom is a part no. 080469-01 REV 01, if that
means anything to anyone, as marked on its paper
label.  The later sigma board does not have the
problem.  Oh, well, if I have to run it with a
KA630 at slo-poke gait, so be it....(:+\\...

There are two diodes, one looks like an ordinary
silicon rectifier and one looks like a zener of
some sort, possibly, off pin 19 of the 74ls240
at position V2 on the board.  Those come off
the J6 pin 10 of 10, and are in parallel.



More information about the TUHS mailing list