Wiring a volume pot into a JAMMA harness

[Phetishboy]

Can you wire the speaker wires on a JAMMA harness to a volume pot? I'm trying to run my speaker wires through a volume pot but I'm using a JAMMA harness. The volume pot I have is from an Atari game. It has three wires going into it and of course speakers only have two wires. Where is the 3rd Wire from? I assume it must be From the ARII. Since I'm not using an ARII, how do I wire the JAMMA speaker wires to the Atari volume pot? Is this possible?

 

[chopperthedog]

You want to use a rheostat type control since the signal is amplified. Something like this: https://www.amazon.com/dp/B00F1YT3I0/ref=cm_sw_r_cp_apa_i_FHERDb192JKP1


good day.

 

[andrewb]

The answers to everything you're asking here (and in your other thread) is in the Kangaroo schematics. Just copy how the wiring is done there. It's in the main wiring diagram, and the page that shows the details for the service panel.

 

[Phetishboy]

The answers to everything you're asking here (and in your other thread) is in the Kangaroo schematics. Just copy how the wiring is done there. It's in the main wiring diagram, and the page that shows the details for the service panel.

So I assume speaker + for JAMMA is 'speaker' on the Atari schematics and speaker - on the JAMMA harness is 'speaker return' on the Atari harness? So one goes to the left tab and one goes to the right tab on the volume pot. What about the brown wire that goes to the center tab. I'm not quite understanding that one.

 

[andrewb]

So I assume speaker + for JAMMA is 'speaker' on the Atari schematics and speaker - on the JAMMA harness is 'speaker return' on the Atari harness? So one goes to the left tab and one goes to the right tab on the volume pot. What about the brown wire that goes to the center tab. I'm not quite understanding that one.

Look at the main wiring diagram in the schematics, and this breakout for the service panel (also in the same doc).

 

[Phetishboy]

Look at the main wiring diagram in the schematics, and this breakout for the service panel (also in the same doc).

I have, several times. The brown wire runs from the component wiring connector to the speaker. I don't see where it Actually originates. The only other reference to a brown wire runs in a loop from C to 18 on the small edge connector. It does not show that brown wire loop connected to the main brown wire that runs to the speaker. Is the brown wire just a regular ground wire?

 

[andrewb]

I have, several times. The brown wire runs from the component wiring connector to the speaker. I don't see where it Actually originates. The only other reference to a brown wire runs in a loop from C to 18 on the small edge connector. It does not show that brown wire loop connected to the main brown wire that runs to the speaker. Is the brown wire just a regular ground wire?

Brown runs from pin 3 of J29/P29 (which is the service panel connector), through J40/P40 and P31/J31, to the speaker, along with white.

See this page (and the one adjacent to it) in the schematics. (Sorry, I can't blow it up larger here at the moment.)

 

[Phetishboy]

Brown runs from pin 3 of J29/P29 (which is the service panel connector), through J40/P40 and P31/J31, to the speaker, along with white.

See this page (and the one adjacent to it) in the schematics. (Sorry, I can't blow it up larger here at the moment.)

Yes I know, I have the schematics in front of me. What I'm trying to figure out is, if orange and white are speaker +/-, what is the brown wire? Where does it originate? What is its function? What signal does it bring?

 

[andrewb]

Yes I know, I have the schematics in front of me. What I'm trying to figure out is, if orange and white are speaker +/-, what is the brown wire? Where does it originate? What is its function? What signal does it bring?

The brown wire originates on the pot itself. It is the volume-adjusted speaker signal (i.e., the 'output' of the pot).

Orange goes into the pot, brown comes out. White is the common speaker ground that ties everything together.

 

[Phetishboy]

The brown wire originates on the pot itself. It is the volume-adjusted speaker signal (i.e., the 'output' of the pot).

Orange goes into the pot, brown comes out. White is the common speaker ground that ties everything together.

Aha! I'm getting it now. The problem is, I have 2 incomplete harnesses here, one from a Kangaroo and one from a Dig Dug, but each one has the brown and white wires cut and sections of those wires removed, so I couldn't tell where they were supposed to go. The schematics, while starting to make more sense now, were a little hard to read for a non-electronics repair guy. Thanks for you patience.