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Mark-8 boards on ebay

falter

falter

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Vancouver, BC
Wondering what you guys make of these and if they are legit:

http://m.ebay.ca/itm/302083673875?_mwBanner=1

The seller cancelled the auction. I did try to ask if they had some proveneance to back up whether they were original or not. I have seen some reproductions that got pretty close to original look. Wondered what you guys thought, and also what original bare boards would likely be worth? I'm prepared to go all the way if these are original and they ever come up again.
 
They appear vintage to me - the only thing that gives me pause for concern, is the apparent shininess of the plating. The plating on most vintage PCBs, have acquired some amount of tarnish over the years. However the substrate appears to the be vintage, and that would be expensive to fake. I would want to get a view in person, before dropping a load of dough on something likely to be as expensive as those could become. Other things to check for, is unplated holes, as original Mark- 8 boards did not have plated holes.

My guess is that the auction was pulled because someone offerred a lot of money for the set.

regards,
Mike Willegal
 
I was about to post about these boards, but since you already did, I'll just add a reply.

The seller contacted me about a month ago, after having bought several boards at an auction. These included some older and fairly rare unbuilt OSI boards, which is how he found me (through OSIweb.org). He put these up on Ebay, and asked me to let anyone who may be interested know about them, which is why I'm posting here. As far as I can tell, this is a complete, real, genuine set of bare Mark 8 boards.

I see he has re-listed the boards:

http://www.ebay.com/itm/MARK-8-circuit-boards-build-your-own-70s-vintage-computer-kit-/291890554372

Dave
 
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Cool. Any thoughts on value? The only Mark-8 auction records I've found are 8-9 years ago and around $5200 for a complete system. I'd happily drop $5k on these (it'll kill my vintage budget for a year or two) if they're real.. not like I'm gonna get them anywhere else.
 
One other question.. if you wanted to 'fake' the substrate.. how would you do that? I was hoping to just build my own Mark-8 using the plans.. but I hate the look of modern PCBs. I was wondering if someone out there can reproduce something that looks closer to vintage than that.
 
And one final q.. would it be bad for value/crime against history to try and build these into a system? Given that they look to be unspoiled new?
 
I'd been looking at Mark 8's during the past few days. These PCB's certainly look like the originals but I'd imagine they would go for big bucks. As for building them up into a complete machine, that's what they are for. Go for it! However, I guess I'm only saying that as I won't be able to afford them and if I could I'd probably chicken out on putting a soldering iron to them :)

I know there were some replica boards available a few years ago but does anybody know of anybody still selling board sets? I built a SCELBI 8B using a set of Mike's boards the other year and really enjoyed it. Would be nice to add a Mark 8 to my replica collection.

Cheers,
Dave
 
Yeah. I'm kinda torn.. if those are original they are pretty close to pristine.. how many pristine as-sold original pcbs are you likely to encounter? Feels like anything you did to them would take their value down, especially if you screwed anything up. And even if you built them into a machine it'd never be an 'original' Mark-8.. it'd be more like a new Delorean. Plus some original parts just aren't available as I've learned with my TVT project.

Hmmm. I had this debate when I saw an original set of TVT boards that I narrowly missed. $38 though. But even then, I was torn between 'oh it'll be an original TVT' and 'no.. it'll still be mostly a repro from 2016 and now no one will be able to see how the original boards came from factory.
 
falter said:
One other question.. if you wanted to 'fake' the substrate.. how would you do that? I was hoping to just build my own Mark-8 using the plans.. but I hate the look of modern PCBs. I was wondering if someone out there can reproduce something that looks closer to vintage than that.
Click to expand...

Faking substrate on boards without a solder mask is actually easy. It is not easy on boards that have a solder mask. Yellow modern boards can be dyed by boiling them in dye solution. They can even be tarnished using an oxidizer. I'm always very careful with valuable vintage boards that do not have a mask. You have to compare them to a known set to see if they have the same flexibility, colour tone and finish. This is very hard for Mark-8 systems since the boards were really made by many different companies with many different quality and manufacturing of boards.

Cheers,
Corey
 
Thanks Corey. I find with the new PCB stock I have they are a bit too brown.. but also the finish is very clean on one side. Just looks too modern. I'd like to learn more on how to get closer to a vintage look.. not to pull a scam but just so my replicas look better.

I'm assuming making those pcb manufacturer marks isn't hard by comparison to boiling dye into the fibreglass?
 
I wonder if you could sandblast one with a fine media before dying to make it look more like an older board. I think with low pressure the copper shouldn't blast off.
 
I'm really surprised there isn't like, 'vintage copper clad PCB stock' out there somewhere. There's virtually everything else but that. Ought to be a business there for someone enterprising enough.

Out of curiousity -- I've heard it said before that finding Mark-8 ICs and parts would be prohibitively difficult.. does anyone out there know which parts in particular are the toughest to get? I noticed there's not much in the way of 1101 RAMs, etc for example.
 
falter said:
Out of curiousity -- I've heard it said before that finding Mark-8 ICs and parts would be prohibitively difficult.. does anyone out there know which parts in particular are the toughest to get? I noticed there's not much in the way of 1101 RAMs, etc for example.
Click to expand...

I think the tricky ones are the Signetics 8267's and 8263's
 
Moonferret said:
I'd been looking at Mark 8's during the past few days. These PCB's certainly look like the originals but I'd imagine they would go for big bucks. As for building them up into a complete machine, that's what they are for. Go for it! However, I guess I'm only saying that as I won't be able to afford them and if I could I'd probably chicken out on putting a soldering iron to them :)

I know there were some replica boards available a few years ago but does anybody know of anybody still selling board sets? I built a SCELBI 8B using a set of Mike's boards the other year and really enjoyed it. Would be nice to add a Mark 8 to my replica collection.

Cheers,
Dave
Click to expand...

Falter and Dave,

well if they are original, and they do look that way, spending up to $5k on the boards is one thing; but then you would need to find Guaranteed NEW OLD stock of the ics to use. That includes correct period date codes.

And certainly considering how RARE these blank boards are to come by, I would be checking, then doing a 'burn cycle time' run on, every IC on a quality IC tester before soldering them in place.

If the original uses IC sockets then you don't need to do the above step, but many early machines simply had the ICs directly fitted.

Then there is the issue of getting the period connectors and the matching interconnecting cable.

In my view, it matters NOT, if you built the machine in the 1970's or in 2016, IF and that's a big IF you use 100% original period parts that were all made in 1970's; then that machine is not a reproduction.

There are rare times via a Garage finds, you come across a sealed 'original kit' of some item, from the way back in the past.

So if you assemble and complete that 'kit' using only the tools and skills of the artisans from that past time, then I feel its no different than making it within a year or 2 of its manufacture.

Now one point I would say, is from when I built my first computer kit, a Motorola MEK6800 D2 in 1976, to now 2016, when I am about to build a brand newly designed surface mount component, Analog Computer, my electronic skills over that 40 years have vastly improved. ( well I still occasionally make the stupid mistakes).

So now if I was to get a brand new, un-assembled complete Motorola MEK6800 D2 kit, it would NOT end up being built exactly the same as my first one, 40 years back; as I cannot UNLEARN my computer and electronics skills.

So in this D2 kit example, if I could get a un-assembled D2 kit now and built it up, WOULD it be an original or a replica ???
 
inotarobot said:
Falter and Dave,

well if they are original, and they do look that way, spending up to $5k on the boards is one thing; but then you would need to find Guaranteed NEW OLD stock of the ics to use. That includes correct period date codes.

And certainly considering how RARE these blank boards are to come by, I would be checking, then doing a 'burn cycle time' run on, every IC on a quality IC tester before soldering them in place.

If the original uses IC sockets then you don't need to do the above step, but many early machines simply had the ICs directly fitted.

Then there is the issue of getting the period connectors and the matching interconnecting cable.

In my view, it matters NOT, if you built the machine in the 1970's or in 2016, IF and that's a big IF you use 100% original period parts that were all made in 1970's; then that machine is not a reproduction.

There are rare times via a Garage finds, you come across a sealed 'original kit' of some item, from the way back in the past.

So if you assemble and complete that 'kit' using only the tools and skills of the artisans from that past time, then I feel its no different than making it within a year or 2 of its manufacture.

Now one point I would say, is from when I built my first computer kit, a Motorola MEK6800 D2 in 1976, to now 2016, when I am about to build a brand newly designed surface mount component, Analog Computer, my electronic skills over that 40 years have vastly improved. ( well I still occasionally make the stupid mistakes).

So now if I was to get a brand new, un-assembled complete Motorola MEK6800 D2 kit, it would NOT end up being built exactly the same as my first one, 40 years back; as I cannot UNLEARN my computer and electronics skills.

So in this D2 kit example, if I could get a un-assembled D2 kit now and built it up, WOULD it be an original or a replica ???
Click to expand...

I'm not sure one could ever get everything 100% vintage with a new Mark-8 build. Somewhere along the way you're going to get tripped up by modernity. I've had all kinds of problems with vintage caps, ICs with my TVT. It's taken 3 years just to get 80% of the way there. I even ran into an issue with the *wood* for the sides.. the wood they would have used for a prototype-similar case in the 70s was very different from wood harvested today. And on it goes. :)
 
Klyball said:
I have some original unbuilt osi boards , and I made replica's so I could leave the original boards unbuilt and could play around without worry of wrecking them http://www.vcfed.org/forum/showthre...ld-or-not-to-build/page2&highlight=superboard

I would do the same here (if I could afford to buy them)
Click to expand...

Well, I think unbuilt OSI boards are probably less rare than unbuilt Mark-8 boards. I wouldn't have a problem building one if I needed to. But these.. I don't know.. I was all gung ho until I started thinking about it. What it would mean to alter their originality by putting an iron to them, or worse if I damaged them? The thing about an unbuilt kit is once built, it can't be unbuilt. There is value to having examples of things as they arrived to people back in the day. These probably belong in a museum. They're just too perfect to screw with, if they're real. Kind of hoping they aren't. :)
 
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Chuck(G) said:
Well, suppose you rolled up the circuitry into a small FPGA?

If it works the same way, what's the difference?
Click to expand...

The difference is the LOOK, the FEEL, and even the smell of the old parts overheating, when you have accidentally install the wrong value component or installed one ic in back the front.

And finally there is the MOST important difference.

Most of today's suitably skilled electronics/computer younger foke, can build a system like a D2 in small FPGA, and get it running properly.

BUT how many of them have the skills and for that matter, the patience, to put together a back planed, 6 board system like say an Altar or S100 or EXORcisor Bus machine, and get all the board address and on board jumpers correct; then create or patch an O/S to suit. ?

I doubt more than 0.5% of the current trained computer techs /engineers could. Or more correctly would want to. "My Grandpar did it so whay should I ?" they say.
 
That was one other thing I meant to ask. *Are* there Mark-8 examples out there known to have *not* been built from the kit boards, but rather via the plans? I know the artwork was available in the plans so it was theoretically possible to make your own boards.. wondering if anyone did.
 
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