Tempest super zapper not working

78whiteorbs

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Put it in test mode and all buttons tone out and respond . Removed wires from button jumpered there to no avail. When further and jumpered the yellow and black wires at the molex and still nothing.

What's next?
 
Check to see if Pin 11 of the LS157 (@D6) goes low when you press the SuperZap button. If that checks out, check Pin 9 of the same LS157 (@D6) to see if it goes low when you press the button. Lastly, confirm that Pin 13 of the Pokey (@C/D2) goes low when you press the button. If all this checks out, that suggests a bad Pokey.

If anything mentioned prior to Pin 13 of the Pokey does not check out, then work backwards to isolate either a bad LS157 @ D6, or a wiring issue between the control panel connector and the edge connector, an edge connector problem, or a broken trace between the edge connector and Pin 11 of D6.

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Swap the two Pokeys. (Or just replace the one that is for the Zapper at C/D2, if you have a good spare.)

Or just pull, clean, and reseat that Pokey first, as it could just be dirty chip legs.
 
Check to see if Pin 11 of the LS157 (@D6) goes low when you press the SuperZap button. If that checks out, check Pin 9 of the same LS157 (@D6) to see if it goes low when you press the button. Lastly, confirm that Pin 13 of the Pokey (@C/D2) goes low when you press the button. If all this checks out, that suggests a bad Pokey.

View attachment 824514

Swap the two Pokeys. (Or just replace the one that is for the Zapper at C/D2, if you have a good spare.)

Or just pull, clean, and reseat that Pokey first, as it could just be dirty chip legs.
Clean and reseated and it didn't do anything.

Swapped with 2 known good pokeys off my centipede board stash That made none of the 4 buttons work(fire ,Zap, player 1 player 2)

Weird?
 
Clean and reseated and it didn't do anything.

Swapped with 2 known good pokeys off my centipede board stash That made none of the 4 buttons work(fire ,Zap, player 1 player 2)

Weird?

If you put another Pokey in the board and it didn't produce the same results, I would question whether that Pokey is 100% good.

Be aware that because a Pokey works in another board (that is not the same game), that doesn't necessarily mean it's 100% good. Different game boards use Pokeys differently.

The only way to compare apples to apples would be to take a Pokey from another Tempest board (and put the suspect Pokey into another known-good Tempest board).

You may have other issues with the address or data busses getting data out of the Pokey. Or something with the LS157. Or, C53 could be bad. (You can desolder and lift one side of it, to test that.) Or test the resistance across C53, and see if it's the same or different than what you measure across C50/51/52. They should all be the same. If C53 is different, it's bad.

That's actually a common issue on Atari boards, those input caps can go bad and basically turn into resistors.
 
Sweet.

Also, you might not want to toss that Pokey. It may only have one bad input, and the rest of the chip may be ok. If you put it in another game board that doesn't use that input, it may work ok. At $60+ a pop, it's worth the chance.

(But you should at least label the chip to say inputs P3/P4 are bad on Tempest.)
 
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