[GreenKeys] Kleinschmidt Drum Printer

[David I. Emery]

On Sun, Oct 03, 2010 at 11:42:25AM -0400, Duncan M. Brown wrote:
> There was recently comments about a Kleinschmidt "drum printer". 

	I was one of the folks who posted info about this...

	The ones I had came from the Honeywell Computer surplus outlet
in the Boston area in around 1974-75... they must have had 50 of them
from some Honeywell minicomputer project that got canceled or
upgraded... and were selling them brand new in box very cheap.

	I do remember seeing them occasionaly at hamfests after that,
never seemed to sell.

	As I remember it (and this is a LONG time ago) they were just
the printer with no keyboard except some illuminated control buttons
(line feed, form feed, on line etc)... and interfaced through a somewhat
non standard TTL level interface (maybe bit parallel or similar, not
regular serial or 20 MA)... 

	These took fan fold paper, I think perforated type with holes on
the tear strips on the side... and did have some kind of form alignment
capability (eg a form feed).

	They were for 8.5 inch wide forms I think (eg 80 columns, but
memory is awfully faint at such removes)... certainly not the wide fan
fold computer paper of the day... 

	They were battleship gray table top mounting units... and
definitely NOT military nomenclatured type milspec equipment but a
commercial OEM product. I forget whether they were badged Kleinshmidt or
not, might have been badged Honeywell... but the manuals (they came with
manuals) definitely said Kleinschmidt...

	There was no paper tape equipment with these printers at all.

	Internally they were a classic drum printer (I think with an
ASCII character set - upper case only - but maybe some fruity symbols
for some of the less common punctuation characters so familiar to C
programmers)...

	As someone else said they had a two hammer print head that moved
back and forth on a rail in front of the drum which was behind the
paper... presumably driven by a servo motor of some kind (or maybe just
a stepper).

	And behind the print mechanism there was box of cards with the
electronics on it... early TTL era parts... 

	As I remember it they would print at 30 CPS (eg 300 WPM) or
maybe faster if driven using the pacing capability in the parallel
interface to feed the thing characters when it wanted them.

	I later (in the mid 90s) acquired some documentation of the
communications systems aboard SAM 27000 - the AF-1 of the day - in the
Nixon/Ford era of the early 70s and it showed two of these sorts of
Kleinschmidt printers... not clear if exactly the same but basically
very similar.   Whether those were a military nomenclatured version I
don't immediately know. - the manuals I have might have that info
somewhere I suppose if I can find them.

	I think we had one printing at one point in the 70s, but by the
time I got around to building the right interface I had found some
Teletype 40 chain type printers that were MUCH faster and did standard
upper and lower case too and never did much with the Kleinschmidts at
all.   It is very very remotely possible that a partner in crime from
that era still has one, I got rid of mine when I got rid of a lot of 70s
minicomputer gear in the mid 80s...


-- 
  Dave Emery N1PRE/AE, die at dieconsulting.com  DIE Consulting, Weston, Mass 02493
"An empty zombie mind with a forlorn barely readable weatherbeaten
'For Rent' sign still vainly flapping outside on the weed encrusted pole - in 
celebration of what could have been, but wasn't and is not to be now either."