tempest monitor/pcb issue-not sure?

tron guy

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Ok so I was over at my buddy portkey's house checking out some games.

His tempest wasn't working.

So we get to work and first thing test voltages on the arII. They are all good. We subbed in my known working a/rII that I brought, no change.

spot killer is on-no neck glow, no chatter from the monitor. We tested all frame mounted transistors to see if they were shorted to the frame-none of them were.

The game does not play blind, or make any sounds when going into test mode. (not sure if it should, but no sounds whatsoever).

The player 1/2 buttons are solid red-lit.

He had a backup tempest board thought to be non-working/partially working, we swapped in the aux. board with no main board-no change.

So.......
I have 2 working tempests at my house. I brought his board home. I want to test it, but I don't want to mess up my monitor or anything by testing it.

What is the best course of action for me to test it? IF it doesn't work, it's going to andrewB anyway, I just wanted to see if I could check it out before we send it.

Also, for future reference, if I take my working tempest board over to his house, we can drop it in his cab to see if his monitor comes up huh?

Also, no blown fuses anywhere on the monitor or in the cab.
 
Life would be much easier if you owned an analog scope. :cool:
(To test the unknown logic board; unplug your working monitor; see if the game coins up, plays and makes sounds).
 
Life would be much easier if you owned an analog scope. :cool:
(To test the unknown logic board; unplug your working monitor; see if the game coins up, plays and makes sounds).

That is what I told portkey I thought we could do.


Concerning the scope-I don't want to repair everything. I've chosen g07's as my specialty, but I can work on any monitor. Board repairs-I'm honored to give cdjump my money, and soon to be andrewb as well. 😀

Thanks for the advice.
 
If I had to make a first-order guess, I'd say his game board and monitor both have issues. No neck glow suggests an monitor issue (or at least power). Not playing blind is very likely a board issue.

I would not plug an unknown board into a good monitor, without checking it on a scope first.

If you want to try something that may give useful info, you could power his board up in your cab, but with your monitor unplugged. (Just unplug from the main harness, then power up the board as usual.) My guess is that it will do nothing, and give a solid light like the other cab, but if you get anything other than that (e.g., playing blind), that would suggest other issues with his cab, like harness, edge connector, or power.
 
If I had to make a first-order guess, I'd say his game board and monitor both have issues. No neck glow suggests an monitor issue (or at least power). Not playing blind is very likely a board issue.

I would not plug an unknown board into a good monitor, without checking it on a scope first.

If you want to try something that may give useful info, you could power his board up in your cab, but with your monitor unplugged. (Just unplug from the main harness, then power up the board as usual.) My guess is that it will do nothing, and give a solid light like the other cab, but if you get anything other than that (e.g., playing blind), that would suggest other issues with his cab, like harness, edge connector, or power.

Ok so I just make sure the 12 (or15) pin molex is not connected to the monitor and I can test away?

Thanks

He has 2 boardsets that likely need repair so look for a pm on those. Heck I need to send in my 90% working pcb with clays kit as well. (Works almost perfect but cant play vortex).
 
To play Vortex you must jumper WDDIS to ground. It was an early prototype that didn't clear the watchdog frequently enough.
 
Yep, the 15-pin Molex connector is power + signal, so unplugging it disconnects everything to the monitor, and you can power up the cab with it unplugged no problem. If the board is set to freeplay (and working), you should get the blinking start buttons, and be able to play blind.

Just be careful when reconnecting the monitor later, to make sure none of the pins on either side are pushed in or pulled out at all, which can cause bad connections, which can lead to other badness.

I like to use DeOxit on those connectors especially, as it cleans the contacts, but also lubes up the plastic a bit, so both halves seat together better when connecting, and also unplugs more easily.
 
To play Vortex you must jumper WDDIS to ground. It was an early prototype that didn't clear the watchdog frequently enough.


I thought that was true of Aliens, but not Vortex?

IIRC, I thought I recall playing Vortex without needing to disable the watchdog (as I recall seeing the attract screen, which is really the coolest thing about it, IMO.)
 
If I had to make a first-order guess, I'd say his game board and monitor both have issues. No neck glow suggests an monitor issue (or at least power). Not playing blind is very likely a board issue.


Start LEDs solid on mean the PCB isn't booting. I've seen this happen when the big blue goes bad. It could also be the power-on reset, CPU, or ROMs. Hit the reset button on the PCB and see if it comes up. Otherwise, pull and reseat ROMs and sub a known good CPU.

Might have monitor issues, but sometimes it can be hard to see if there's glow happening or not. I'd start with the boardset.
 
You are correct sir.

So now the question is why would that one game not run if the others are working? I have the ROM from Clay if you need it.



You have the vector ROM, or the main ROM? (Or both?)

IIRC, you had given me a link a while back to the VROM you had, but if I'm remembering, I tried it and it didn't work, and I think I got one from brzezicki, and that worked for me, and I sent you a copy(?) Sorry if I'm remembering it wrong, but I thought that was how things went. I know I fixed one kit for another KLOVer by burning a new VROM, and I still have that known-good file, which I think I sent you. I just want to avoid confusion if there are multiple VROM files around.

The main ROM is a square PLCC flash, which is soldered to the board. Have you dumped that one too? It's harder for most folks to replace (or even check), unless you remove it, and you have the right adapter to program a new one.

I've had a plan to build an adapter to replace the CPU, which breaks most of the wires to a 28-pin DIP socket, which would allow me to read the flash with a GQ-4X (maybe having to solder a few wires to the PLCC directly, but not all of them). I haven't gotten a chance to build and try it yet though.

I did see one kit (from another member here), which wasn't playing some of the selections, and was resetting (Vortex and Vbreakout, I think), but worked ok for the other selections. I saw that it had a huge lump of solder shorting several of the pins on the main ROM, which looked like it came from the factory that way.

It had a QA sticker on it saying it had been checked, but my guess is that they only powered it up and verified that the main menu worked, and didn't go so far as to verify every game fully (which would be a lot more work). Removing the solder bridges fixed it, so that's something to check, if you're seeing the same behavior.
 
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