asteroids-no sounds when shooting

tron guy

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I tried to do a little research using the search feature but didn't come up with anything.

Everything else on the game seems to work, except for the sound it is supposed to make when the player fires/shoots.

edge connector is not burnt anywhere. I put a rebuilt power supply in the game.

what would be a logical series of steps to troubleshoot this?

or what is the known fix??????
 
Do all the other sounds work fine? Explosions, the "thump thump", thrust, extra man beep, saucer noise, saucer shooting.
 
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Next would be to check the AR board.

the a/r board is rebuilt

Do all the other sounds work fine? Explosions, the "thump thump", thrust, extra man beep, saucer noise, saucer shooting.

I am almost certain all other sounds work. I need to check to see if the thrust sound works, but I am very certain it does.

It's just the firing that has zero sound.
odd huh?
 
It's just the firing that has zero sound.
odd huh?

Not really. The sound in Asteroids is "discreet", so there is a seperate analog circuit that makes each sound. There's not too much to it really. From memory, a 555 timer, a 4016 bilateral switch, an inverter, and some passives. Try getting the schematic from arcarc.xmission.com The asteroids schematics are some of the best I've ever seen. I'm pretty sure the sound is on the last sheet (2B). You may need to determine which dash-number PCB you have (-01 thru -06) to get the correct IC location references.

http://arcarc.xmission.com/PDF_Arcade_Atari_Kee/Asteroids/Asteroids_DP-143-7th-02B.pdf
 
There's also quite a lot of usefull information here:

http://www.ionpool.net/arcade/asteroidtech/asteroidsrepair.html

I had a board ages ago with missing alien saucer fire (which is essentially the same circuit design) I think it was a duff 555 timer. Back in the day I asked around but these days I'd probably just look at the schematics and replace the relevant items if they are cheap and easily available (which, generally they are) as there aren't that many.
 
This is what I pulled from the link you just gave me. Can someone tell me where the 12v reguilator is on the board, I may as well try to fix it.
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2. Problem: Missing Sounds.

Suddenly several of the game's sound effects have vanished. Specifically, the ship shot, saucer shot, and saucer flying effects have degraded into various quiet clicks, pops, and buzzes, though they activate at the proper moments and for the proper duration's. From looking at the schematics it seems strange to me that these would all fail simultaneously, while leaving the thump, explosion, and new life sounds intact.

Fix: 12V regulator had failed, and was only putting out around 4 volts. This was the cause of the problems, and was easy to fix.

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Someone had mentioned in my battlezone thread (where I discussed this problem briefly) that I should check positions C37, C40,C47,C48,C50,C51 for a broken cap, etc. All of them looked good.
 
Can someone tell me where the 12v reguilator is on the board, I may as well try to fix it.

It'll be near the edge connector. It will be a 3-leg component that looks like a transistor (TO-220 package). It will likely be labeled "7812" or similar.

I recommend measuring the 12V before replacing the regulator.
 
Dude,

This is how you test all the voltage regulators;

picture.php
 
Nice picture, but it doesn't show the 12V regulator, which is up closer to the edge connector...
 
thanks for that schematic

I forgot to mention (not sure how relevant it is), that when I hit the fire button, I can hear the slightest of a buzzing sound of some type through the speakers. It registers something, or another way to say it, I can hear a little click or something through the speaker, but it's nothing like normal sounds.
 
thanks for that schematic

I forgot to mention (not sure how relevant it is), that when I hit the fire button, I can hear the slightest of a buzzing sound of some type through the speakers. It registers something, or another way to say it, I can hear a little click or something through the speaker, but it's nothing like normal sounds.

Well that does mean something..

Sounds like the shipfireen is probably good.
C48 could be bad, that will cause wrong sounds, and or clicks, and nothing.

If you have a logic probe you can probe the outputs while hitting the fire button to see if the signal is getting through.

My best guess without putting this on a scope is the 555, or one of the Tant caps. Most likely the 555, quick trip to Radio shock.
 
Well that does mean something..

Sounds like the shipfireen is probably good.
C48 could be bad, that will cause wrong sounds, and or clicks, and nothing.

If you have a logic probe you can probe the outputs while hitting the fire button to see if the signal is getting through.

My best guess without putting this on a scope is the 555, or one of the Tant caps. Most likely the 555, quick trip to Radio shock.

are you saying radio shack will have the parts I need?
 
I'd replace the 4016 (you should use a 4066) an M9. All that does is gate the sound....turn it on and off. Start there, if that doesn't take care of it look around the 555 timer chip that creates the sound and its associated circuitry.

Just a note on the 4066 chip, it is static sensitive. So don't work in a super dry environment without a ground strap on yer wrist to drain off any static charges.
 
So is the 555 at M9 the one I am changing? I see several 555's on the board.
 
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