House of the Dead no audio

[johnfromsd]

Crackling sound through speakers when volume pot is adjusted. Sound amp is verified working in Virtua Cop 2. Guns, lamps, monitor and game all running as they should. I've read online that all four LEDs should not be on simultaneously, but not sure what to try next.

 

[irepairsega]

Yes all four on solid means sound is dead. Did you acquire unit like this or did it just do in on its own? If it did it on its own and was working, I generally rule out ROM Bd. Then pretty much anything goes in sound section of CPU Bd. Make sure absolutely zero corrosion. Check what 5v is at Game Bd. If over 5.3 I would suspect the socketed GAL is dead. Feel for hot parts elsewhere in sound circuit. I have see a lot of TDA1386 fail on other pcbs so I would not rule that out.

 

[johnfromsd]

Recently acquired the game in this condition. Getting 5.18v at the board where it's labeled 5v input. Boards look clean and free of any corrosion.

 

[Toobin]

Does house of the dead 1 have a separate sound board, and if so where is it located?

 

[johnfromsd]

Yes; the sound board is in the bottom of the cabinet.

 

[Toobin]

Thx

 

[mecha]

should be the one with the RCA jacks on it. I can open the game at work and get flash photography.

EDIT: I stand corrected, the sound board is in the cage somewhere. thank you for posting this thread, I discovered the cage fan died and everything is not good here right now. lol

for anyone wondering the +5V and ground wires are in fact yellow and white Sega colors

EDIT: for posterity Sega red = +12V also

quite certain I notated all of this here: https://www.arcaderepair.net/mechas-essential-power-supply-guide-remastered/

also for anyone wondering, the power supply voltage is 5.20V and it's 4.92V (which is entirely sufficient unless irepairsega Ken says otherwise!) at one of the few through hole chips on the CPU board, so about a .30V drop is normal from the power supply to the boards in the cage.

 

[Toobin]

Awesome, thx

 

[johnfromsd]

 

[mecha]

yeah, that's just the amplifier

your power supply is of the unobtanium variety for about the last 6 years or so