Are they? Perhaps the PDP-10 uses them in their header panels? If that's the case, I could harvest some from the system in Kiel - it will never run again, and I've been given the advice to harvest lamps by the DEC guy where I got my lamps. In fact he is the man who serviced that particular system. And he gave me the advice while handing me a lamp pulling tool... So if those lamps are really rare and could get into use, I could try to negotiate the harvest. Hm... Did you ask there? Hm. I have 26 OL-1. And 80+ OL-2... Wouldn't it better to find some lamps? I wonder what I used to replace lamps on the pdp8/l - I have completed at least one front panel. Ah, oh, I think I took them from another 8/l that's completely in pieces. So if the 8/i uses the OL-1 lamps, the 8/l probably does as well. In that case I would also be very interested to get some more of those.

Has anyone tried the currently-available CM7370 in an 8/I or RK05? This bulb is suggested as a substitute for the OL-1 on Vince's web page. The suggested substitute for the OL-2, the CM7371, works wonderfully in an 8/E. They are plenty bright, and they will last longer running at undervoltage. An 8/E that I received in working condition arrived with a full complement of CM7371 installed by its previous owner (a machine shop). I suppose the big issue is matching the brighness. You probably don't want to substitute the bulbs piecemeal, and repeatedly unsoldering/soldering soldered-in bulbs is damaging for the circuit board. Best to replace them all at once, or install socket pins (scavenged from machined-pin IC sockets) as found in the 8/E. Some technical information regarding operating incandescent lamps at other than their nominal ratings can be found here: http://www.wamcoinc.com/Oshino/Oshino_lamps-Overview.htm --Bill

Hi Rich, I've been told that the University of Kiel's PDP-10 installation originally was largest in Europe. In the early 90s, the system went out of service. At that point they already discarded masses of equipment. I've been told of many tons of disk drives, tape drives and so on. The Kiel museum/collectors society who were tracking the University's computing department's "output" for many years saved a complete system consisting of two KI10 (not sure, but older than KL10) processors, memory, drum memory, peripheral controllers, and some peripherals. About 25 racks. And a row of RP02/03 disk drives. And tons of cables and documentation. That roughly describes what has been kept in basements over the last years. Since last year, the FH Kiel (technical college) took over the whole collection that contained the pdp10. They are currently in the process of compiling a permanent exhibition of computing history in an old WW2 shelter that is currently being prepared for that. They have to deal with massive space limitations compared to the volume of existing stuff in the collection. So they started to sort out things. Their interest is do display stuff, not to run stuff (but at least a pdp8/e will be runnable, perhaps we repair the 8/i as well). They are in touch with the guy who maintained the machine (the guy with the lamps). He selected about five cabinets and one RP02 disk drive for the exhibition. The exact minimum of stuff that can be called "pdp10 system, complete". The rest has been given away to collectors. I personally saved some stuff (RP drives, RS04 drives, CR10 card reader), the biggest part went to collectors who have in mind to get the stuff working again. The documentation for the pdp10 (or most of it, It will probably my job to dig through the remaining docs of the collection) has been thrown away with respect to the fact that the system will "never run again". A very lucky circumstance was that Erik Brens was standing next to the trash when that happened. So the recycling took place on eBay instead of a paper mill. could it be The "never run again" comes from the DEC service engineer. He told the Kiel official people (and me) that it would be possible (if the docs and cables etc. were still there, of course) to get the system back to work. But for that he would need at least one year of work (3 month to move the system from one building to another, with 4 people!!). He is sure that nobody else would be able to get it running. And he is not interested to do it as there also is no interest and money to get the system running again. So it will be there, nice and clean. And never run again. Hopefully the guys who got the major part of the system will be interested and skilled enough to get their stuff working. That would be a resurrection of great historic value! Best wishes, Philipp

The ususal reason for that pronouncement is the backplane is summarily messedup beyond belief. In some cases due to shorts or other "errors" large sections of wire wrap being cooked. (I presume this is an early 10 and not a 20). That also means that any board plugged into it is suspect as well. Many hours of proble and verify, unpowered! Repairable yes, lots of work big time yes. Worth fixing during it's commercial days, rarely. At a minimum it should be kept intact as an example if parts cannot be used to restore another. Allison Tony Duell wrote:

Are there any DEC 10's running elsewhere? If not, then this one could become the only one. If there are others. Then talk to whoever runs them. At least their knowledge will be more current than your disinterested retired board swapper. Regards Rod Smallwood -----Original Message----- From: cctech-bounces at classiccmp.org [mailto:cctech-bounces at classiccmp.org] On Behalf Of Allison Sent: 26 October 2009 20:13 To: General Discussion: On-Topic Posts Only Subject: Re: Kiel PDP-10 [was RE: pdp8/e frontpanel lamps] The ususal reason for that pronouncement is the backplane is summarily messedup beyond belief. In some cases due to shorts or other "errors" large sections of wire wrap being cooked. (I presume this is an early 10 and not a 20). That also means that any board plugged into it is suspect as well. Many hours of proble and verify, unpowered! Repairable yes, lots of work big time yes. Worth fixing during it's commercial days, rarely. At a minimum it should be kept intact as an example if parts cannot be used to restore another. Allison Tony Duell wrote:

<ahem> http://www.livingcomputermuseum.org Our 2065 runs nearly 24x7 and is accessible on the Internet. We're restoring a 2020 soon. And we'd LOVE to get our hands on a KI-10 (and a KA, too!) - we'd get those running. That's what we do. :-) -- Ian ________________________________________ From: cctalk-bounces at classiccmp.org [cctalk-bounces at classiccmp.org] On Behalf Of William Donzelli [wdonzelli at gmail.com] Sent: Tuesday, October 27, 2009 12:11 AM To: General Discussion: On-Topic and Off-Topic Posts Subject: Re: Kiel PDP-10 [was RE: pdp8/e frontpanel lamps] Apart from the obvious, a few KS10s remain operational in private hands, although not always powered up. It would not surprise me if one or two KL10s or KS10s were still in real world production environments as well (even after the Great Purge). -- Will

Amen. Rich Alderson Vintage Computing Server Engineer Vulcan, Inc. 505 5th Avenue S, Suite 900 Seattle, WA 98104 mailto:RichA at vulcan.com mailto:RichA at LivingComputerMuseum.org http://www.PDPplanet.org/ http://www.LivingComputerMuseum.org/

From: "Philipp Hachtmann": Well, they are rarer at least in my personal experience. It is of course possible that there are thousands out there that I don't know about. If the PDP-10 panels are 54-08458 Peripheral Indicator panels, then those use OL-2. The only thing that I am positive uses the OL-1 is the 8/i (and presumably the PDP-12?). I didn't ask at Wamco, and reviewing the correspondence, it is possible that they didn't answer my questions because they wanted their disti to do it, rather than because they really didn't know. It ended up not mattering much -- there are other bulbs made by Chicago Miniatures that are probably close enough to the original OL-1. I suppose I should be happy with the CM7370 for the OL-1, and the CM7371 for the OL-2. Though they are getting hard to find these days too. No, the 8/i uses OL-1, but the 8/L uses OL-2, like the 8/E. Here's a pointer to my (somewhat dated) page on the subject: http://www.so-much-stuff.com/pdp8/bulbs.html Vince