On Mon, 29 Mar 1999, Tony Duell wrote:
What you have
then is equivalent to an upgraded Model III, since the
Model 4 upgrade was essentially a mobo replacement, all other pieces
were the same between the two machines. (Well, floppy vendors
Not quite. The keyboard is different (the model 4 one has extra keys on
it). Although you can use the wrong keyboard with either machine - the
extra keys are in unused positions on the 8*8 matrix on the Model 3 and the
keyboard cable pinout is the same.
You're right, I forgot the Mod III didn't have those (years since
I've actually looked at a III in fact).
The Model 4 _disk machines_ had a sound board as
standard. No idea why
this was a separate board - all it consisted of was a 7474 D-type (half
used) + a transistor driver + a minispeaker. As there was an unused half
of a 7474 on the CPU board right next to the sound connector. It would
probably have been cheaper to put the few extra components on the CPU
board. Go figure.
Don't recall ever noticing the sound board. I wasn't all that
hardware hacking oriented in those years.
changed back
and forth a couple of times). Though some Mod 4s with
green tubes got through the system, I'm told (I never saw one).
Do you mean that? I thought all Model 4's had green CRTs. Mine certainly
does (early S/N non-gate array board)
Total mind-fart on that one. That's what I get for composing
messages at the end of a sleepless weekend. It's the white
screen desktop 4s that were rare, the 4p started out with white
then went green. I did know one guy who dropped his 4p and broke
the tube, went with a third-party amber replacement.
Model 3's have white CRTs as standard, although
there were aftermarket
replacements with green or amber screens.
Advertised in every epidode of 80-Micro.
--
Ward Griffiths
"the timid die just like the daring; and if you don't take the plunge then
you'll just take the fall" Michael Longcor