27 Feb
2008
27 Feb
'08
3:28 p.m.
One thing that hasn't been mentioned. His system
may be
unintentionally over clocking. I've seen systems where the
crystal will take of at an overtone. It is even possible that
Interesting. I had an HP9820 where the master clock seemed to be running
at 19MHz (should e 8MHz), but that turned out to be due to the crystal
being cracked in half (I carefully cut the can off it), and the 19MHz was
the free-running frequcny of the TTL gates in the oscillator circuit.
Needless to say the machine didn't work at all...
the crystal is broken and running at some higher
frequency.
Just a thought
I would guess that the most likely harmonic to jump to would be the
third. Now :
1) I dout very much any machine would be designed to run at a third of
the clock rate that it could run at. Yes, you have some margin, you don't
push things to the limit, but a factor of 3? So if the clock jumped to
the third harmonic, most likely the machine wouldn't work at all
2) Even if it did, I think you'd notice it was running 3 times as fast as
normal...
-tony