battlezone no sound

tron guy

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I have replaced both edge connectors, changed the big blue, cleaned up and replace the fuses, rebuild the power supply board, added the braze kit.

no audio

I measured voltages throughout both boards just now on the test points. All of them were good except 1. The +22 on the aux board tested at .7v. I tested the legs of the 470uf 25v capacitor right next the the +22 test point and it gave me .7v. Whereas when I tested the capacitor next to the +5 test point I got +5.3 the same as the test point.

Will simply changing this capacitor do any good?
Should I try it and check back?

What is involved with rebuilding the audio section of this board?

I did try a brand new speaker and still got no sounds.
 
I measured voltages throughout both boards just now on the test points. All of them were good except 1. The +22 on the aux board tested at .7v. I tested the legs of the 470uf 25v capacitor right next the the +22 test point and it gave me .7v. Whereas when I tested the capacitor next to the +5 test point I got +5.3 the same as the test point.

Will simply changing this capacitor do any good?
Should I try it and check back?

Sounds like a logical step to try.

What about the volume pot? Wires good?
 
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The 22 volts originates on the Audio/Regulator board. Do you have 22VDC on it? There should be a test lug on it.

Edward
 
1. Measure ohms across speaker tabs.
2. Measure ohms on pot or clip across and bypass it but it could be loud lol.
3. Check voltages like they are saying.
4. Rebuild audio section.

Do you have a Star Wars or Centipede you can take the AR Board out of and try ? They use the same one as BZ.

Edit: You have a Tempest to MH conversion, that should use the same AR board if I am not mistaken ( if it uses the Tempest AR board)
 
The 22 volts originates on the Audio/Regulator board. Do you have 22VDC on it? There should be a test lug on it.

Edward

edit this part: I do have good voltage on the a/rII.

1. Measure ohms across speaker tabs.
2. Measure ohms on pot or clip across and bypass it but it could be loud lol.
3. Check voltages like they are saying.
4. Rebuild audio section.

Do you have a Star Wars or Centipede you can take the AR Board out of and try ? They use the same one as BZ.

Edit: You have a Tempest to MH conversion, that should use the same AR board if I am not mistaken ( if it uses the Tempest AR board)

yeah the mh/tempest power board has been rebuilt as well as this one.
I will measure +22 on the main board, if it's there I guess I don't need to swap power boards? I guess it couldn't hurt to do it anyway.

wiring looks good going to the adjustment pot. There is a seemingly unused black wire with a quick disconnect on it hanging around the sound pot. The sound pot appears to be in good shape with all wires intact.
If someone had a picture of their sound pot that would help



maybe it's worth mentioning that there isn't even the slightest hint of sound. No speaker cracking, no hum. It's truly silent.
 
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http://crazykong.com/pins/Battlezone.pin.txt


pinout from crazykong.

am I imaging things or do they have the wiring backwards on the aux board?

Concerning pins 21 and 22 from the main board what do sense- and sense+ do?

First of all... be very very careful with any pinouts found "online". I've been burned twice by them. Do youself a favor and swear them off. Go straight to the source: the schematics.

Next, the +SENSE and -SENSE lines are on the main PCB, not the aux board. The pinout you linked shows the AUX board first, then the main board. And according to the Atari schems, pin 21 is +SENSE, and 22 is -SENSE. However, the sense lines relate to the +5V supply (specifically, allowing the ARII to regulated based on the +5 at the PCB). I don't think any lack of sound issue is related to the sense, if the game works fine (without sound).

+22V on the aux board is essential in the audio. It powers the LM324s that pre-amplify the generated signals the a level appropriate for the ARII to amplify.
 
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Just went and confirmed +23.9 on the a/rII, still +.7 at the +22 test point aux board and across the legs of the capacitor right next to it.
 
First of all... be very very careful with any pinouts found "online". I've been burned twice by them. Do youself a favor and swear them off. Go straight to the source: the schematics.

Next, the +SENSE and -SENSE lines are on the main PCB, not the aux board. The pinout you linked shows the AUX board first, then the main board. And according to the Atari schems, pin 21 is +SENSE, and 22 is -SENSE. However, the sense lines relate to the +5V supply (specifically, allowing the ARII to regulated based on the +5 at the PCB). I don't think any lack of sound issue is related to the sense, if the game works fine (without sound).

+22V on the aux board is essential in the audio. It powers the LM324s that pre-amplify the generated signals the a level appropriate for the ARII to amplify.

yeah not sure why I looked at that, didn't do anything based on it. thanks for the reply.

Can you manually jump the +22 to your aux board just to verify that you only have a connecter/wiring problem?

I could run a wire from the somewhere with +22(main board?) and run it to the test point on the aux board to see if audio suddenly shows up? is that what you have in mind?
 
ok, I have no idea where I am supposed to jumper the +22 from to get it to the test point on the aux board. help anyone. :)


At this point is there any chance the capacitor is bad and that's the issue, in reality? Can the bad cap cause me to get .7 instead of 22v?
 
Can you manually jump the +22 to your aux board just to verify that you only have a connecter/wiring problem?

ok, I have no idea where I am supposed to jumper the +22 from to get it to the test point on the aux board. help anyone. :)

Is there a 22V test "loop" on the AR or main PCB that you can grab the 22 V and run a wire to the 22V test "loop" on the auxially board


At this point is there any chance the capacitor is bad and that's the issue, in reality? Can the bad cap cause me to get .7 instead of 22v?

If you have a spare cap why not try replacing it. It would at least rule something out.
 
I believe that voltage is 23v AC not DC, I would bet you have an issue with a POKEY more than anything, try swaping around the 4 pokey chips on the AUX board to see if the problem changes, you may gain sound but notice something else now doesn't work correctly.

Sometimes the test menu picks up the bad POKEY and sometimes is doesn't, and maybe it just needs to be reseated, check back with what you find.
 
I believe that voltage is 23v AC not DC, I would bet you have an issue with a POKEY more than anything, try swaping around the 4 pokey chips on the AUX board to see if the problem changes, you may gain sound but notice something else now doesn't work correctly.

Sometimes the test menu picks up the bad POKEY and sometimes is doesn't, and maybe it just needs to be reseated, check back with what you find.

what chips are the pokey chips? are they labeled specifically or do you know their positions?
thanks for the input.


out of curiousity if you say the 22v is ac not dc, should I flip my multimeter to ac and test it. IF it fries the multimeter I have a back up. :)
 
I'll look up the socket # for you but in the mean while, go test that voltage on AC and even if it was DC it will not harm your meter.

(edit)Here's the Sockets;

K2, H/J2, F2, ED2

they should be the 4 largest chips on that board.
 
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Show me on the schematic where it has 23vac going into the Aux board ?

All i see is 22vdc on pin 3. You are making this way more complicated than it needs to be.
Check voltages before you worry about chips.

just my .02

edit: pin 1 of connector P10 on your AR2 board should have 22VDC coming out of it, it goes right to pin 3 on the Aux board. Put your black on ground somewhere and your red lead on those one at a time and see if you have 22 VDC at each location, pin 1 on connector p10 and pin 3 at your aux board.
 
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Show me on the schematic where it has 23vac going into the Aux board ?

All i see is 22vdc on pin 3. You are making this way more complicated than it needs to be.
Check voltages before you worry about chips.

just my .02

I told him to check the volage first, did I not? I know there is +23 and -23V Ac from the power transformer, so I'm not sure about it being DC going into the AUX board but 'm going to look right now.
 
Show me on the schematic where it has 23vac going into the Aux board ?

All i see is 22vdc on pin 3. You are making this way more complicated than it needs to be.
Check voltages before you worry about chips.

just my .02

edit: pin 1 of connector P10 on your AR2 board should have 22VDC coming out of it, it goes right to pin 3 on the Aux board. Put your black on ground somewhere and your red lead on those one at a time and see if you have 22 VDC at each location, pin 1 on connector p10 and pin 3 at your aux board.

I could go check that now, I swapped a couple of the pokey chips? as I pulled them I realized that one of them had the bent leg I found last week. It fell off, so I soldered a new piece of metal on in it's place. It held. Anyway, did the chip swap, spot killer, swapped them back, spot killer.

can I guy get 4 new pokey chips?


going to test those spots now arc
 
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