From: jones@pyrite.cs.uiowa.edu (Douglas W. Jones,201H MLH,3193350740,3193382879)
Newsgroups: alt.sys.pdp8
Subject: Re: PDP-8 Collectors
Date: 5 Nov 92 19:54:26 GMT
Organization: University of Iowa, Iowa City, IA, USA

From article <Bx946L.KCM@uxa.ecn.bgu.edu>,
by mgcbo@uxa.ecn.bgu.edu (Charles B. Owen):
> I think lots of the machines are still floating around (???)
	Yes they are.  Over the summer, I picked up three Omnibus machines
	(model E, F and A) at U of Iowa surplus, and I know where there are
	a number of model I and L machines on campus, yet to be sent to
	surplus.  I suspect that most big research universities are similar,
	with various machines mothballed or in storage closets in various
	places on campus.  Look in the back storerooms of chemistry,
	engineering, or psychology labs for such things.
> 
> Is anyone else doing this, as just a hobby (not maintaining one for
> business use)?
	I have a model E and a model F in my study at home, neither works
	yet, but I ought to be able to get one up fairly soon (given the
	time to track down some bugs in the front panel).  If I had a spare
	RX8E board, I'd be able to build two complete useful systems, since
	I have two RX01 dual diskette drives.

	At work, I've talked our department into providing a home for a
	1966 vintage PDP-8, and I have a small group of students starting
	the job of figuring out whether it is safe to plug it in and try
	turning it on (such wonderful questions as: are all the flip-chip
	modules plugged into the right slots, and what cables go where?)

	There are also very likely to be many industrial users of PDP-8
	based systems.  Just last month, I was talking to a man from an
	Alcoa plant, and he said that they were still using NC machines
	that were real antiques.  I'd lay even odds on an antique NC
	machine being PDP-8 based!
> 
> How available is software that I would not have to pay DEC for?  Much PD
> available?
	There's a young but growing PD repository of PDP-8 software at
	ftp.telebit.com.  I'm not clear on whether I have the right to
	distribute the ancient DEC source code I have, but I'll be finding
	out.

> For obsolete hardware, it would almost make sense for DEC to
> give the stuff away.
	Yes.  So far, DEC has been quite nice about granting permission
	to reprint their documentation, and I imagine they'll let us do
	the same to their ancient software, but I have not confirmed
	this.  Remember that DEC only discontinued the PDP-8 product line
	in 1990 with the demise of the DECmate III+, so some PDP-8
	software may still be considered to have current market value,
	and DEC probably still has a number of customers with service
	contracts and other money making relationships who are running
	DECmates and end-of-the-run Omnibus machines.
> 
> Any problem maintaining these systems?  I am very good at electronics,
> so I can handle anything I can get parts for.  But, are there many
> custom parts that are difficult to obtain?  (particularly mechanical
> parts)  DEC still support?  (Reasonably)
	Everything can still be found commercially, much of it on the
	reconditioned second-hand market.  Individual boards for the
	OMNIBUS models of the PDP-8 sell for about $75, on the price lists
	I've seen.

	If you get a classic or straight -8, parts are no problem, since
	everything is discrete component, and plain transistors and diodes
	will never go out of style.  If you get an OMNIBUS machine, there
	are custom SSI and MSI chips used that are out of production.  If
	you ever need to replace such a chip, you'll have to hunt down
	one of a small stock of spares or cannibalize a chip from a
	different board.  I have collected every OMNIBUS board I could get
	my hands on for this purpose, including a number of real junkers
	that were hand kluged I/O interfaces for one-of-a-kind devices.
> 
> Any idea what used systems are costing?  I an talking about the real
> PDP-8's, not the Rainbows.
	I bought a PDP-8/E, and 8/F and an 8/A plus two RX01 units for a
	total of $25.  I spent $35 for one relay rack, and got the other
	free.  Of course, when you buy surplus, you never know whether or
	not it will work, and the good prices only happen when there's
	nobody else bidding on the stuff.

				Doug Jones
				jones@cs.uiowa.edu