2 Sep
1999
2 Sep
'99
2:31 a.m.
After I wrote this remark I got to thinking . . . the model I was dogging
was a flatbed not quite the right size for "B" format but had analog inputs
rather than RS-232 or HPGL. It was a 72-something, but my aging memory
can't produce the "something" as it once did. Several fellows I knew had
snagged them and I spent literally weeks with each of them trying to make
them perform repeatably. They looked and smelled solid, but didn't behave
that way. Even when they were more or less operational, the pen speed was
very slow.
The 74xx series, by way of contrast, was more or less like a real plotter
though it was just a toy . . . sort of a stopgap while they developed a
useable printer with which to do the same thing. The 75xx models actually
behaved like real plotters. That tray-fed tabletop 7550 was the smalles in
this series, IIRC, but it had eight pens and could plot quickly and
accurately as could its bigger bretheren. There are some folks who were
sorry to see these dinosaurs pass, but anyone who's had to wait 45 minutes
for one to plot a "D"-sized drawing will tell you the ink-spitters are a
gigantic improvement.
Dick
-----Original Message-----
From: Eric Smith <eric(a)brouhaha.com>
To: Discussion re-collecting of classic computers
<classiccmp(a)u.washington.edu>
Date: Thursday, September 02, 1999 1:49 AM
Subject: Re: HP DraftMaster I
ROMS
Joe <rigdonj(a)intellistar.net> wrote:
> Sounds like a HP 7221 plotter with paper feed. I have one of them and a
> 9874 that's similar but has a HP-IB inteface. Someone dropped the 9874 on
> one corner and bent the whole thing out of kilter. I've tried everything
> but I can't get it to feed paper right. The framne is too heavy to try
and
straighten
out. Perhaps if I took it to someone that has a puller for
straightening car frames .....
I think you must be referring to the HP 9872. They sold basically the
same plotter as three models:
HP 7220 - RS-232 serial, compact binary language
HP 7221 - RS-232 serial, HP-GL, same hardware as 7220 but with different HP 9872 - IEEE-488 (HP-IB), HP-GL
Different letter suffixes denoted the generation of the plotter, and
whether
it had the roll feed (e.g., 9872 A/B/C without, and
9872 S/T with). Early
generations had four pen stalls, and later ones had eight.
Note that these were the first HP-GL plotters, and the language evolved
some minor differences that prevent some modern software from working with
them. I built my own serial-to-488 box to use with mine, and my firmware
tweaks the HP-GL when necessary.
"Richard Erlacher" <edick(a)idcomm.com> wrote:
> God be thanked, it's not at all like that miserable piece of junk! If id
> hadn't said HP on it, nobody with more than two grey cells would have
taken
one home.
I can't believe you'd say that about this series of plotters, which were
very well-engineered and solidly built flatbed plotters. Are you
sure you're not thinking about the 7225, or the much later "consumer"
grit-wheel plotters such as the 7470 and 7475?