Road Show Sound Issues!

[jooky]

Hey guys!
I'm hoping someone on the forum can point me in the right direction with my Road Show. I got it off the recent container in April and only recently got it powered on after changing the power cord cable and changing the jumper settings to N.America as detailed on another thread.

One of the big issues is the lack of sound. I look at the speaker panel and notice that the wires have been cut for some reason.

So I strip them and attach them to each other again - black to black and black/yellow to black/yellow like below:


But as soon as I power on the machine the speakers output this LOUD distorted buzzing sound. It's loud - like something is wrong loud. It's just a buzz, no game sound can be heard. I power it down quickly.

There is no battery corrosion anywhere and the fuses on the sound board look ok:


So I can leave the speaker wires attached but I have to disconnect the connector J2 to the sound board:


And everything else seems to work - game starts and plays, just no sound. Whoever had the game before me probably cut the speaker wires to turn off the loud speaker buzzing. Now its on me to figure it out!

Anyone have any suggestions? I've never had to troubleshoot sound before, it's always just worked! Thanks!

 

[Menace]

It's a sound board issue for sure. You need to figure out if the issue is pre-amp or post. If you have any PCB re-work experience I would say this is a problem you might be able to solve yourself. If you're not comfortable doing PCB re-work, and are not comfortable reading schematics this might be best to have someone with experience look at it. (cough*me*cough) My guess is there is a component failure in the amplifier section.

When you turn the game on and the speakers start to buzz, can you adjust the volume of the buzz with the volume buttons on the coin door? (my guess is no, which again would lead me to an amp issue, not pre-amp)

D

 

[movingpictures]

Sounds like a perfect candidate for the Menace files!

 

[Menace]

Ya, along with all the other repairs that I've finished and got waiting to write up and post. UGH, there's just never enough time in a day...

D

 

[jooky]

I will definitely check those things out tonight and update. Menace I'm pencilling you in as my guru tech help guy! Thanks for the tips so far! Btw how did your 2 zaccaria's turn out?

 

[Menace]

I will definitely check those things out tonight and update. Menace I'm pencilling you in as my guru tech help guy! Thanks for the tips so far! Btw how did your 2 zaccaria's turn out?

Sounds like a plan. If you need my services, the best thing to do is get the PCB to me. From there I can sit with the schematics and troubleshoot, and test in one of my games.

I have still only hauled the ROBOT home, and finally had the motivation to at least haul it into the basement yesterday. Normally by now I would have at least converted the power and fired it up, but I've got a lot of stuff happening right now in my life that is sucking my will to live... I'm hoping to be able to deliver my BH to it's new owner this weekend and pickup MC on the way home. Once I kinda get my life back on track I will most certainly be starting a post about each of the Zacc games here for all to follow.

D

 

[jooky]

I didn't get a lot of time to investigate more last night but I recorded a sample of the buzzing:

http://www.youtube.com/watch?v=QMBe2Uz99tE

I can get into the sound and music test menu but the controls they do nothing. It's just the constant loud buzzing you hear in the video. There's not much I can see in that test menu anyways, its just stuff like "Play Red's theme" or play this other song. The volume control does nothing.

I also tried re-seating all the sound card connectors - 4 molex type and 1 ribbon connector, but it didn't make a difference. The investigation continues...

 

[Menace]

Yeah, if you're not getting any sound board errors on boot-up my previous comment about it being in the amplifier section is probably bang on. (especially where adjusting the volume does nothing to raise and lower the level of the ground buzz. Time to bust out the schematics and your DMM and start looking for things that are not right.

D