Untested boards - do you get lucky?

[edwoodjnr]

I know it is always a gamble when you see a nice clean board for auction on Ebay with a good price. It is rare to see a classic board these days where the buyer states in the description that it is tested and working and generally most of the older boards listed as untested (assumed not working?).

Do you take the gamble assuming you can determine and fix the problem if proved to be not working? It would be an expensive undertaking if the board is from the USA and you aren't able to fix it.

Myself, I recently took the gamble bought a Star Wars PCB set untested from the USA and sure enough it wasn't working. I was able to quickly determine that both the AVG and Sound boards were fine and that there was a problem on the mainboard. The problem was that there were no stars or tie fighters and on the towers stage, no towers. After a bit of research I found that this was likely to be one of these Bi-polar PROM's 7H,7J,7K & 7L or the pseudo random number generator chips and so I swapped the socketed spares left over from the ESB kit I installed on my other working board. After a bit of trial and error I found 7K to be faulty.

I think I got lucky and with a simple fix now have a fully working boardset. Anyone with similar experiences, good or bad?

Also do you know where I can get a spare set of the Bi-polar PROM's 7H,7J,7K & 7L in the UK?

 

[lowlevel]

I got 'unlucky' recently with a killer instinct 2 board.

It shows only a blue rolling line on top of the screen. With and without the hard disk (bad hard disk = the game normally shows a red flashing screen with the sound danger danger)... No clue what could be wrong with it.

 

[smarty]

I 'won' an ebay auction for an untested Missile Command board some years back, turns out it was actually fully working. I got it for a good price too, shame it has since died on me.

 

[Muppz]

bought a job lot of 2 konami boards untested in 1 auction, one was water damaged (legs rotted off of customs) the other works fine so 50% success for me.

 

[stevebm1]

ive bought so called working boards off ebay before that are F@@ked,luckily if they are listed as used,you can get your money back through paypal,if you return the item,I recently had to do that with a terminator 2 board,that was different from the photo,and missing components

 

[ZedEx48K]

I got a bunch once from an old op that all needed testing (and ended up being free), there was a working R-type Leo in there

 

[Alpha1]

I've bought working boards and they have been dead and I've bought dead and faulty pcbs that have worked fine! Crazy world!

 

[Level42]

I've been quite lucky with "untested" boards. Bought a MB set from the US, asked seller if there was any chance it was working. He told me it had been pulled out of a working machine BITD and was put on a shelve ever since so there was at least some chance it was working but he didn't guarantee anything.
Worked and still works like a charm.

Had the chance to buy an Asteroids PCB years ago, seller did not have hardware to test it in, payed 25 Euro and it works great.

Someone tipped me about a SW boardset on a small countries' ebay site.....that was my luck I guess, was the only bidder and it went "under the radar" and I paid about 18 Euro for it. Worked right away although it does so some fluid spill spots. I keep it as my spare set.

Just bought an original Q*bert board from internet, untested. Hooked it up to my Fluke and that is indicating all RAMS are failing which I find a bit hard to believe, maybe buffer IC. Haven't hooked it up to a monitor yet so....we'll see.

 

[ben76]

Its about 50/50 for me. Had some good deals though.... I once got a faulty SF2 boot (not ar$ed) Double Dragon II boot and an original Rezon for about £30 all in iirc I beat Chappy to it by 50p

Also got an untested original Kung Fu Master for £20

I tend to go by the rule that Untested + Jamma = broke and untested + non Jamma = Maybe worth the gamble.

- Ben

 

[IDCHAPPY]

Its about 50/50 for me. Had some good deals though.... I once got a faulty SF2 boot (not ar$ed) Double Dragon II boot and an original Rezon for about £30 all in iirc I beat Chappy to it by 50p 

Also got an untested original Kung Fu Master for £20

I tend to go by the rule that Untested + Jamma = broke and untested + non Jamma = Maybe worth the gamble.

- Ben

Aye

.
I did win 10 untested and 6 of them worked. 3 were Footy Champ though

 

[Alpha1]

I tend to go by the rule that Untested + Jamma = broke and untested + non Jamma = Maybe worth the gamble.

Good advice.

 

[cmjones01]

I've had mixed luck too. I've never bought a JAMMA board but ben76's rule makes sense - some non-JAMMA boards are just too hard to test casually without the right wiring loom, and I've had both a (bootleg) Zaxxon and (real) Centipede bought very cheaply on eBay which Just Worked.

Fixing them is a big part of the fun for me, but I've had a few boards with an almost unbelievable number of faults on them and I can't understand how they got into that state! Sometimes every example of a particular chip has failed on the board, but often there's a whole pile of unrelated problems. I can only imagine that somebody mis-wired the power at some stage, or left the board out in a thunderstorm...

The satisfaction gained from bringing a basket case back from the dead is great, though, even if it's not worth it financially!

Chris