About to wade into a Breakout...

Scucci

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I'm getting no +5 on the boards, traced it back to a bad diode in the power section.

As soon as I find my roll of diodes I'll be replacing both (bridge with center tap)... after that, there's no telling what I'll be getting into.

Does anyone on here have any experience with the boards? As there is no CPU I'm not sure if that's going to make it harder or easier to work on... I mean will the thing try to run but just have faults in the areas related to the bad components (score not being kept, ball movement, etc etc etc)?

Either way... should be a learning experience, would just like some help from anyone that's had to go through it before as well.
 
I've had a lot of experience fixing these kinds of boards. It's really very easy.

You will need the schematic, a TTL databook (or the Internet), a multimeter, and a logic probe.

Basically, get the power supply working, verify you have good power to the chips. If there is one section not working correctly, find that part on the schematic, start at the beginning of that area and work your way through with the logic probe. If it's completely dead, start at the clock crystal and work your way through.

Pay special attention to 7474 flip flops. I seem to find a lot those that have, er... flopped. I think it might have been a bit of a marginal design.

Note that you can also very easily run the board on the bench, you can rig it up to a switcher, and use a television set, old computer monitor or other composite video display to see what's going on.

-Ian
 
I've had a lot of experience fixing these kinds of boards. It's really very easy.

You will need the schematic, a TTL databook (or the Internet), a multimeter, and a logic probe.

Basically, get the power supply working, verify you have good power to the chips. If there is one section not working correctly, find that part on the schematic, start at the beginning of that area and work your way through with the logic probe. If it's completely dead, start at the clock crystal and work your way through.

Pay special attention to 7474 flip flops. I seem to find a lot those that have, er... flopped. I think it might have been a bit of a marginal design.

Note that you can also very easily run the board on the bench, you can rig it up to a switcher, and use a television set, old computer monitor or other composite video display to see what's going on.

-Ian

Does it put out enough of a signal to run the video out to an RCA input on a TV?

I've had this thing in storage for about a year now... and every time I have to check another board and fight the CPU, I just keep thinking "I bet Breakout will be easier since I don't have to deal with the CPU f'ng half this stuff up..."

I finally (about 2 minutes ago) got Breakout inside off the carport... so I'm taking a breather, then I'm finding the diodes (hopefully) and I'll start on her. ... if I can't find the diodes, then I might just as well run +5 from a switcher to the rails and see what happens. ... but I'd much rather find the diodes.
 
Does it put out enough of a signal to run the video out to an RCA input on a TV?
It sure does! You can also connect standard composite video devices to the monitor in the game. Since these old games don't have a test pattern, the easiest way to get the monitor all dialed in (if you have to do a lot of work on it) is to wire it into a DVD player with a disc of test patterns.

"I bet Breakout will be easier since I don't have to deal with the CPU f'ng half this stuff up..."
It is easier. A lot easier.

I finally (about 2 minutes ago) got Breakout inside off the carport... so I'm taking a breather, then I'm finding the diodes (hopefully) and I'll start on her. ... if I can't find the diodes, then I might just as well run +5 from a switcher to the rails and see what happens. ... but I'd much rather find the diodes.

Good luck! How's the edge connector on yours? I've seen several where it's completely cooked, like a Pac board. Mine was so bad that some OP had soldered lamp cord to the board...

-Ian
 
Good luck! How's the edge connector on yours? I've seen several where it's completely cooked, like a Pac board. Mine was so bad that some OP had soldered lamp cord to the board...

-Ian

The 3 pins beside the key'd part on the connector have seen better days. They're completely fried, have been half-assedly repaired. They make contact with the connector... that's enough for me for now. But they will get fully repaired eventually.

The monitor has seen better days as well... it's going to require a rebuild at least. When I turn the machine on the monitor is solid white... but I haven't checked to see if the brightness is just turned up all the way or if something on the board has goofed. I'll worry about that when I get some action out of the boards.

I think this will FINALLY be a machine my mom can play when she's down here. I got a Pac for her... too hard. ICB, too hard. Golden Tee, too hard. Then she talked about liking Asteroids for the 2600... so, got an Asteroids DLX... ... too many buttons, too hard. So... maybe, just maybe, this will be one she can actually play.
 
Waded in and the water's too deep.

I'm getting nothing from the board, but the coin mechs do trigger the counter. So something on there is doing something. But no video from the board, no sound, no nothing.

Who repairs these things?

For the record, I haven't messed with ANY of the ICs, but it looks like a previous owner has done a little something here and there. ... and this was the same previous owner that drilled a hole in my Asteroids Deluxe to put in an external credit switch. (the game has freeplay built into it)

All I've done to the board was replaced the failed diodes in the power supply section with the largest diodes I had on hand. But there seems to be something wonky with the power overall.

I kinda need an "around about" quote upfront as I don't have an actual job and I will have to save up a little before I can send them out.
 
I know nothing about this game and what voltages it requires but if possible I'd suggest hooking up a switcher for testing purposes until you get the original PS working correctly.
 
I know nothing about this game and what voltages it requires but if possible I'd suggest hooking up a switcher for testing purposes until you get the original PS working correctly.

The original PS is built onto the board. Kind of like Pac-Man. It takes in 16.5VAC, uses the center tap on the transformer and 2 diodes to break that down to DC, then has a voltage regulator on the board that drives that down to a steady 5V.

The diodes I replaced and the regulator are getting pretty hot very fast. I checked at the leads to one of the caps and it looks like something is shorting to ground somewhere. ... but that regulator is keeping 5V going to the boards regardless (hence the heat I'm guessing). I'll keep checking and tinkering, but I don't really want to touch any of the ICs as I know that people who repair boards don't like that because they can never really trust the work. (lifted pad under an IC, etc etc)... (although I don't lift pads... but still).
 
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