Re: Fire-Sale PDP-11 update (and request for parts)
On Sun, Dec 6, 2020 at 3:11 PM Fritz Mueller via cctalk < cctalk@classiccmp.org> wrote: > > > On Dec 4, 2020, at 10:41 PM, Josh Dersch via cctalk < > cctalk@classiccmp.org> wrote: > > I realize this is unlikely, but I was curious if anyone has 1) any > > parts of the 11/45 power wiring harness... I can build my own wiring > harness, but if I can save > > myself the trouble, that'd be nice. > > Yeah, I had build my own for my /45 restoration. It wasn't all that bad. > Throw down for a nice ratcheting single-gesture crimp tool for the job and > you'll be glad that you did :-) > > I found wirebarn.com had a nice selection of wire available in > less-than-full-spool lengths, and most of the original colors. I may have > had to fill in a few things from other suppliers (I found it helpful to > stick to the original color coding.) > Thanks, that'll be handy. > > Another tip is that the wire list you see in most of the /45 drawing sets > is actually for the power harness, and not the backplane. The wire lengths > in that list were useful; I cut to those lengths, then started on the > regulator side of the harness, installed in the machine, and bundled and > trimmed to length as I worked my way down the backplane. In the end I had > a reasonably neat fit and very little wasted wire. > Also very good to know, thanks! > > I had the extra wrinkle of having the earlier (serial # <2000) power > distribution system in my /45 (IIRC the wire list was from the newer > system, but it wasn't too hard to adapt it.) > > Do you have the springy steel strip that supports the harness between the > moving and stationary parts of the cabinet? That may require some fab or > improvisation if not. I had one left over from an 11/40 that I was able to > make work well enough with my older style cabinet. > I do, it's a bit rusty. What remains of the wiring harness is no longer attached to it, as the plastic ties holding it in place burned away (along with the rubber sheathing and the most of insulation on the wires themselves.) - Josh > >cheers, > --FritzM. > > >
Re: Fire-Sale PDP-11 update (and request for parts)
> On Dec 4, 2020, at 10:41 PM, Josh Dersch via cctalk > wrote: > I realize this is unlikely, but I was curious if anyone has 1) any > parts of the 11/45 power wiring harness... I can build my own wiring > harness, but if I can save > myself the trouble, that'd be nice. Yeah, I had build my own for my /45 restoration. It wasn't all that bad. Throw down for a nice ratcheting single-gesture crimp tool for the job and you'll be glad that you did :-) I found wirebarn.com had a nice selection of wire available in less-than-full-spool lengths, and most of the original colors. I may have had to fill in a few things from other suppliers (I found it helpful to stick to the original color coding.) Another tip is that the wire list you see in most of the /45 drawing sets is actually for the power harness, and not the backplane. The wire lengths in that list were useful; I cut to those lengths, then started on the regulator side of the harness, installed in the machine, and bundled and trimmed to length as I worked my way down the backplane. In the end I had a reasonably neat fit and very little wasted wire. I had the extra wrinkle of having the earlier (serial # <2000) power distribution system in my /45 (IIRC the wire list was from the newer system, but it wasn't too hard to adapt it.) Do you have the springy steel strip that supports the harness between the moving and stationary parts of the cabinet? That may require some fab or improvisation if not. I had one left over from an 11/40 that I was able to make work well enough with my older style cabinet. cheers, --FritzM.
Re: Fire-Sale PDP-11 update (and request for parts)
On 12/6/20 11:07 AM, John Foust via cctalk wrote: Darn, I thought you'd tell some other tales of what Dale had in his warehouse. What would you like to know? Many of machines are there are from Eric Smith (DEC-20, PDP-12, etc. etc.) I won't go into the details of why Dale is selling them. I should have left my HP2100 boards there. I moved them to a shipping container which was broken into and anything with gold on it was stolen. Dale mostly has arcade games there. I gave my entire arcade collection to Dale and moved and scrapped most of my other stuff that was there over the past five years.
Re: Fire-Sale PDP-11 update (and request for parts)
At 12:41 AM 12/5/2020, Josh Dersch via cctalk wrote: >Thought you folks might be interested in a quick update on my folly here. > >At the beginning of November I drove down to the bay area to pick up the >two fire-damaged PDP-11 systems -- a PDP-11/70 and a PDP-11/45. (I also >made a few other stops and got a few other items, but that's not what I'm >here to talk about...) Darn, I thought you'd tell some other tales of what Dale had in his warehouse. - John
Re: Fire-Sale PDP-11 update (and request for parts)
> On Dec 5, 2020, at 1:41 AM, Josh Dersch via cctalk > wrote: > > Thought you folks might be interested in a quick update on my folly here. > > At the beginning of November I drove down to the bay area to pick up the > two fire-damaged PDP-11 systems -- a PDP-11/70 and a PDP-11/45. (I also > made a few other stops and got a few other items, but that's not what I'm > here to talk about...) > ... > > The 11/45 is considerably further gone. It took a serious amount of heat, > enough for the pig iron frame for the front panel to start melting ( > http://yahozna.dyndns.org/scratch/1170/1145.jpg). It looks pretty bad, but it's not quite as bad as what your words suggest. I doubt that frame is iron. Consider that the rails of the rack are corroded but not visibly warped, let alone melted. I would guess the bezel is potmetal or some other low melting point cheap alloy. Potmetal is a zinc alloy, it melts very easily. paul
Fire-Sale PDP-11 update (and request for parts)
Thought you folks might be interested in a quick update on my folly here. At the beginning of November I drove down to the bay area to pick up the two fire-damaged PDP-11 systems -- a PDP-11/70 and a PDP-11/45. (I also made a few other stops and got a few other items, but that's not what I'm here to talk about...) Over the past few weeks I've gone over the two systems and my assessment is that the 11/70, while completely filthy, is completely restorable. The fire/heat damaged the front panel enough to discolor the plexi and start melting a few switches (http://yahozna.dyndns.org/scratch/1170/1170.jpg) but that's the extent of the damage. My only fear is that the fingers on the backplanes might possibly have some corrosion here and there, but I've started going through and cleaning the boards and the backplane slots and so far I haven't run into anything that looks troubling. The 11/45 is considerably further gone. It took a serious amount of heat, enough for the pig iron frame for the front panel to start melting ( http://yahozna.dyndns.org/scratch/1170/1145.jpg). The front panel is completely destroyed, as is the wiring harness for the power distribution. But... the metal of the chassis and the power supplies seems to have protected the boards and the backplane. There are no melted or even discolored wire-wrap wires on the backplane, and the boards look fine. As an experiment I took the non-11/45-specific boards out of the backplane (a Plessey memory board, an RL11 controller, and an M9301 bootstrap terminator -- this one was right up front where things were the hottest and the handles had started to melt) and tested them in my PDP-11/40. They all work fine. So I think that, maybe, with a LOT of effort, the 11/45 could live again. I'm tackling the 11/70 first (Al kindly sold me a new front panel for a very reasonable price so it already looks 100% better) and once I'm done with that I hope to move on to the 11/45. In the meantime I'm hoping to keep my eyes peeled for parts for the /45. I found a seller on eBay with "restored" H7420a power supplies for $68, with free shipping so I grabbed a pair. I realize this is unlikely, but I was curious if anyone has 1) any parts of the 11/45 power wiring harness, or 2) (really unlikely) an 11/45 front panel in any condition. Well, any condition better than "melted into slag," I suppose. I can build my own wiring harness, but if I can save myself the trouble, that'd be nice. - Josh
