Picked up a pretty nice Tempest today for $150

Yeah, that DC Y value is a little suspect. I'd have to take measurements on mine to doublecheck that, but I don't think Tempest normally goes that high.

Also, I should have mentioned, but make sure you have all of the video pots centered. That should get you a reasonable image, if all else is ok, as it's actually possible to trigger the spot killer by having them grossly misadjusted. You may want to try that, and re-measure. (Also, make sure none of the legs on the pots are broken.)

If the voltages are still off with the pots centered, and it is playing blind, you likely have something wrong in the video section. Could be a bad y-axis DAC, or anything after it. But you really need a scope to get in there and see what's going on, else you can just socket and replace the chips blindly until you see that DC level come down.
 
It's possible that you have a game board problem, and the board is putting out bad voltages to the monitor, which is causing the fuses (and possibly other stuff) to blow. In general, you never want to connect a 6100 to a game board unless you are sure the game board is putting out safe voltages, as you'll just repeatedly blow the monitor.

Test the DC and AC voltages on the XOUT and YOUT test points on the game board. You should have between 0 and 1 volt DC, and roughly 2-3V AC on each. These are not exact values, as they fluctuate a bit during the attract mode. But if you are getting more than 1.5V DC on either, there is a problem.

If that's the case, one quick check is to feel the chips in the video section with the back of your finger, with the game powered on, and the monitor disconnected. The video section is the lower right section, where the adjustment pots are. If any chips are scorching hot, they are bad, particularly the TL081's, TL082's or 1495's. You want to replace those first, and socket them.

That won't be guaranteed to fix it, as chips can be bad and not get hot, but if they're hot they're definitely bad, so start there.


Thank you for this information.
Following this post and trying to learn more about vectors.
 
Thank you for this information.
Following this post and trying to learn more about vectors.



Do a search through my posts, and read, read, read. You can ignore my sale threads, but you'll find a lot of practical info on vector repair, in similar threads where we diagnosed various issues with different games. The deeper you dig, the more you'll find.


Also, if you aren't already aware, see the vector monitor FAQs for more good basic info:

http://www.ionpool.net/arcade/tech/6100_faq.pdf

http://www.ionpool.net/arcade/tech/bw_vector_monitor_faq.pdf

-Andy
 
I am not intimidated by any repair problem nor easily deterred, but I also understand I don't have all the equipment (like a scope) to troubleshoot some components . Should I shotgun a few parts in the X - Y section of the PCB or let a more experienced person repair it?
I am willing to shotgun a few parts if you would give me a educated guess the ones to start with?
 
I am not intimidated by any repair problem nor easily deterred, but I also understand I don't have all the equipment (like a scope) to troubleshoot some components . Should I shotgun a few parts in the X - Y section of the PCB or let a more experienced person repair it?
I am willing to shotgun a few parts if you would give me a educated guess the ones to start with?



Well, here's the thing. It depends on your level of experience and confidence with soldering (as well as your tools to a certain degree).

Shotgunning is tricky with these Atari boards, as they don't have solder mask on the component side, so it's very easy to get shorts (particularly under sockets), and pulled traces, if you aren't familiar with removing chips from these boards.

I have a Hakko 808 desoldering gun, which helps a lot, but doesn't solve the problem by itself. Honestly, even I would be hesitant to try to remove some of these chips with a manual sucker. The traces are very thin, and pull easily, particularly on the top of the board. And you really need to get all of the solder out of the holes, otherwise you'll rip the plated via out of the board when you try to pull the chip.

If you feel comfortable doing it, by all means try. But just be aware that shotgunning is a double-edged sword, as with every chip you remove, you run the risk of either damaging the board, and/or introducing new problems (which will be much harder to detect without a scope). With a scope, this repair in your case would be pretty easy, so it's up to you.

If you do want to try it, the best advice is DO NOT force anything. Add solder to each pin before sucking. And if the pins do not loosen up, don't force them, but instead add back more fresh solder, then try sucking again. Don't try to force any more heat on the pins than what it takes to melt fresh solder back on them.

If I had to do it blind, the first chips I would suspect would be the 6012 DAC, and the final TL082 amp, both in the y-axis chain. It sounds like you're getting signal, but the signal is imbalanced, which can be caused by a number of things (and even possibly digital stuff before the DAC). But the DACs in these are often bad, so I'd be looking at that first. Though realistically it could be any of the analog chips, including the 1495 or TL081 amps, or 13201 switches (though in my experience those failures are less common).

Note also that there are two copies of each chip in the video section, as the X and Y paths are basically the same. So refer to the schematics to make sure you have the right ones.
 
Again thanks Andy for your time and help.
I feel pretty confident desoldering and soldering. I have a good station to desolder. I also know this is a different beast. I am going study and read up on it.
Thanks again, Scott
 
I can't get one for $1000, you get one for $150! Sleep with it!

The one thing I've noticed about Tempests in the Cleveland area is that at times there's a couple that will pop up on CL at the same time then months of nothing. It took me a long time to get the cabaret I wanted and it was definitely worth it.
 
Finally got back on the Tempest. Bought a scope to see whats going on with the PCB and tracked down some issues with the monitor. I need to do some tweeking on the picture, but getting close.
 

Attachments

  • IMG_3340.jpg
    IMG_3340.jpg
    555.3 KB · Views: 58
  • IMG_3353.JPG
    IMG_3353.JPG
    408.6 KB · Views: 21
Last edited:
$150 club....

I can't get one for $1000, you get one for $150! Sleep with it!

I guess you have to be at the right place at the right time. I got a very nice Asteroids Deluxe for $150, lol. Needed a cap kit and header pin reflow and the monitor came back to life. The rest of the cab cleaned up nice and it still has the factory zip ties on the edge connector/pcb so the edge connector has never even been removed before, lol. ;)

It's just being at the right place at the right time. The guy I bought it from wasn't very fluent with repairing them and just wanted it out of his house and it was playing blind so I knew a monitor rebuild or a monitor swap and I would be good-to-go. Luckily I got the monitor working and it looks good!

$150 for this beauty!

MgPdWUk.jpg



How'd I do? lol :D It plays perfectly now and is fully working! What's really great about this deal is that I was actually looking for this game and wanted it bad enough to pay $1500 for it, heh. $150 + some TLC and cleaning, can't beat that with a wooden hammer, lol. ;)
 
Finally got back on the Tempest. Bought a scope to see whats going on with the PCB and tracked down some issues with the monitor. I need to do some tweeking on the picture, but getting close.

Congrats on your $150 steal and getting it working, hehe.
 
Back
Top Bottom