🚀 go-pugleaf

In <65...@helios.TAMU.EDU> mcg...@cs.tamu.edu (Tim McGuire) writes:

>In article <16...@yenta.alb.nm.us> d...@yenta.alb.nm.us (David B. Thomas) writes:
>		...	got the bright idea of hooking a signal 
>tracer to the least significant bit of the accumulator extension (well, 
>actually the panel light for it.)  The result was a lot of interesting
>noises whenever the machine was processing.  

The first computer I ever learned to fix was an (ancient!) Burroughs
B-825(I think), used by the USAF as an early warning system.  This 
guy was a real MONSTER!! Power consumption was    65 KW/Hr !!!!
Each cabinet was 4'x4'x6-7'tall, and there were between 6 & 12 !~!!!

I remember that the memory cabinets were really sophisticated; they
 were dual memory units - each cabinet had 2  ....64Kb..... _CORE_	
memory units.   WoW! .:-)

Anyway, the main console had a speaker and amp in it; the input to 
the amp was from the LSB of the main accumulator (register, for you
youngsters out there!).  After some time, you could tell the 
approximate state of the machine by listening to the "tune" coming
from the console.


Years later, when I worked on various DEC PDP based equipment,
we would often take an FM radio into the computer room, tune it
up & down the dial until we found the CPU.  This actually turned
out to be a valuable troubleshooting tool, at times.



-- 
-------------------------------------------------------------------------------
Michael G. Hart   ha...@blackjack.dt.navy.mil /  mh...@dtrc.dt.navy.mil
DTRC/DoD			  |  "Wherever you go, there you are."- me
DISCLAIMER: If you want the Navy's opinion, talk to Secretary Cheney.
--
-------------------------------------------------------------------------------
Michael G. Hart   ha...@blackjack.dt.navy.mil /  mh...@dtrc.dt.navy.mil
DTRC/DoD			  |  "Wherever you go, there you are."- me
DISCLAIMER: If you want the Navy's opinion, talk to Secretary Cheney.