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PDP-8 M847 & M8320

I have no idea what is going on here. I have purchased from sdinet in the past and there was nothing unusual about the transactions.

That is a nice looking 8/e front panel but not that nice.
 
Wow - both of those auctions have a lot of bidder activity as well... What's so special about this board? Are the three ICs unobtainium?
 
pbirkel@gmail.com said:
www.ebay.com

DEC Digital Equipment Corporation PDP 8 M847 & M8320 | eBay

M8320 – KK8E Bus Loads. M847 – MI8E Hardware Boot Strap Loader.
www.ebay.com

I do not find this auction to be credible. Do you?
Click to expand...

It appears that at least two people or organizations fought over it with a last minute snipe snatching it for a cool US$810.
Unless the PDP-8/e bus load and boot loader boards are going to be used to keep mission critical machines running in national security or space launch environments it seems hard to justify that kind of money for two dumb boards. Even in those environments by now you would think they have replaced old PDP-8/e machines with modern systems or at least emulated machines.
I am really curious about these bidders. If anyone has any insights please speak up.
 
All I can tell from looking at the bidding history is that there is at least one other bidder willing to pay $800 for an M847. I've not seen eBay obfuscate the bidders by saying "private listing" before this or we would know how much bidder #3, #4, and #5 was willing to pay as well.

There are possibly a handful of mission critical vintage machines still in service. If a machine was in service at a nuclear reactor I bet they would not permit Roland's M847 as a replacement. For something like a CNC machine it should be fine even if mission critical. But the question is how would they find out about it?

The winner was probably someone like me, only a lot richer or perhaps just a lot less patient. Or maybe a rich patient in a mental institution. Oh another one of those silly English words that means two radically different things.
 
Just looked at the M8320 bus loads board that is stand alone and with 45 minutes remaining it is over $500. I sort of understand the M847 but an M8320??? These are nothing special and every machine has one.

Makes no sense!
 
OMG - the 8/e front panel PCB sold for US$960 with three people fighting over it. :eek:
The 8/e plastic front panel sold for twice the price of what Rod Smallwood charges for them.
Even the RF shield - essentially a blank PCB - sold for US$103.50. Heh?

I think Doug may be right that some crazy/drugged/super-rich/drunk people are on the loose. 😜

Seriously though, maybe there was some publicity about the 8/e which we are not aware off?
Otherwise even for Ebay these prices are unusually high.
 
I have heard from a reliable source that the reason for the crazy high bids for the M8320 bus loads is not that crazy at all.
Apparently, due to Western sanctions, there is a severe shortage of 1/4 W resistors in 1500 Ohm and 470 Ohm in the Russian supply chain.
To keep the Russian nukes, tanks, submarines and fighter aircraft going they are forced to salvage these precious resistors from vintage computer boards.
The M8320 is a gold mine for these with 46 x 1500 Ohm and 41 x 470 Ohm resistors on it.
Lucky that they got that many for a bargain basement price of US$800.

😜
 
thunter0512 said:
OMG - the 8/e front panel PCB sold for US$960 with three people fighting over it. :eek:
The 8/e plastic front panel sold for twice the price of what Rod Smallwood charges for them.
Even the RF shield - essentially a blank PCB - sold for US$103.50. Heh?

I think Doug may be right that some crazy/drugged/super-rich/drunk people are on the loose. 😜

Seriously though, maybe there was some publicity about the 8/e which we are not aware off?
Otherwise even for Ebay these prices are unusually high.
Click to expand...
Some people get their teeth into an auction and their brains fall out. I've literally seen people bid on an open box set of Klipsch speakers to the point where it sold for more than an identical new factory sealed with warranty set from BestBuy.

From experience, I've learned to first survey, not just completed listings, but completed & sold listings, to get an idea what is a reasonable selling price. But sometimes even that isn't much help.

How much would a reasonable price be for a complete, running 11/70? They just don't pop up that often.
 
Depends a lot on your definition of "complete". Do you mean just a BA11-F, front panel, a set of CPU modules, a suitable serial I/O module, and two H7420 with a reasonable set of regulators and wiring harness? No FPU, clock, MJ11 or MK11 memory, or Massbus controller(s)? No rack(s)? No RM03? No power controller? Purple-panel or blue datasystems panel (it does seem to make a difference to some bidders)?
 
DDS said:
How much would a reasonable price be for a complete, running 11/70? They just don't pop up that often.
Click to expand...
"It depends" is of course a correct answer, "whatever two people agree to" is another answer that is correct.
If you have and don't want or want and don't have a 70, they aren't all that helpful though.
I'm no expert, but as an owner and parts buyer, here's what I've observed:
Because the 70 is made up of some common parts and some rare parts, the whole can be worth a lot more or less than the sum of the parts, so that does make it a lot harder to pin down than say a 11/44. In particular the floating point and memory subassemblies make a huge difference. No memory means a non-working machine and it's very rare to see memory for sale divorced from the machine. A complete and working(!) machine is worth a lot more than a complete project. The are big and heavy to pack and ship, consider one in your neighborhood worth at least $500 more than one you have to ship.
Front panel $450-750 of a complete/working one, deduct $30-50% for broken or missing parts but still mostly intact.
Timing board, some FPU boards $200+/ea
Other CPU boards, $50-100/ea
Unibus boards $5-100/ea
Power supply bricks $20-60/ea on condition.
PS racks $50-100/ea
Chassis/backplane $50-500
rack w/o skins $100-200 w/skins might be 2-3X.
Header $50-200
memory box cables $50-200
Power controller $30-50
BA11 unibus box $150-400
complete memory box? My guess is a grand easy, could be 2-3K to someone with a CPU who needs it.

A tested, working, complete system, integrated and with peripherals could very easily be a $10-20K thing these days is my guess, and something that appears to the casual observer to be a 70 but is broken and missing important parts could easily be worth under $2K.
That's still a huge range and I'm sure some will have issue with some of my numbers, but they are at least from things I've seen sell in the last few years so not implausible.
 
Teletech said:
"It depends" is of course a correct answer, "whatever two people agree to" is another answer that is correct.
If you have and don't want or want and don't have a 70, they aren't all that helpful though.
I'm no expert, but as an owner and parts buyer, here's what I've observed:
Because the 70 is made up of some common parts and some rare parts, the whole can be worth a lot more or less than the sum of the parts, so that does make it a lot harder to pin down than say a 11/44. In particular the floating point and memory subassemblies make a huge difference. No memory means a non-working machine and it's very rare to see memory for sale divorced from the machine. A complete and working(!) machine is worth a lot more than a complete project. The are big and heavy to pack and ship, consider one in your neighborhood worth at least $500 more than one you have to ship.
Front panel $450-750 of a complete/working one, deduct $30-50% for broken or missing parts but still mostly intact.
Timing board, some FPU boards $200+/ea
Other CPU boards, $50-100/ea
Unibus boards $5-100/ea
Power supply bricks $20-60/ea on condition.
PS racks $50-100/ea
Chassis/backplane $50-500
rack w/o skins $100-200 w/skins might be 2-3X.
Header $50-200
memory box cables $50-200
Power controller $30-50
BA11 unibus box $150-400
complete memory box? My guess is a grand easy, could be 2-3K to someone with a CPU who needs it.

A tested, working, complete system, integrated and with peripherals could very easily be a $10-20K thing these days is my guess, and something that appears to the casual observer to be a 70 but is broken and missing important parts could easily be worth under $2K.
That's still a huge range and I'm sure some will have issue with some of my numbers, but they are at least from things I've seen sell in the last few years so not implausible.
Click to expand...
It was kind of a rhetorical question. But suppose you wanted, and had the budget, to set one up as the crown jewel of your PDP collection, how much?

And I believe you are correct when you say "It depends."

OTOH, how much would be a 'good" price for a "wall hanger" front panel, or a "guaranteed working" front panel if it was the last piece you needed to complete your restoration project.

All of those criteria, and more, come in to play on ebay auctions. And of course, a certain amount of madness.
 
DDS said:
It was kind of a rhetorical question. But suppose you wanted, and had the budget, to set one up as the crown jewel of your PDP collection, how much?

And I believe you are correct when you say "It depends."

OTOH, how much would be a 'good" price for a "wall hanger" front panel, or a "guaranteed working" front panel if it was the last piece you needed to complete your restoration project.

All of those criteria, and more, come in to play on ebay auctions. And of course, a certain amount of madness.
Click to expand...
Ah, see I have it in mind as some are popping up for sale but missing important parts, I also have one that someone was interested in buying, AND was considering building another with my spares, so it's very much a real question for some of us these days. At the end of the day, they *are* really cool machines.

Of course, those considerations figure heavily when shopping for any parts. I have a CPU board set, front panel, and many power supplies. I got them for spares but would like a 70 in both colors, so a backplane and memory are worth more to me while other parts are worth a lot less. So,"it depends".
 
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