Life Force sound issue

beigemore

Member
Joined
May 1, 2010
Messages
55
Reaction score
1
Location
Texas
I recently acquired a Lifeforce pcb and it works great except for a sound issue.

The game isn't playing any of the voices at all. Playing the game, all of the sound effects work but it never says when you pickup the power ups or when you're supposed to dodge something (like in the second level when the voice says you can't destroy the asteroids). I've gone into the test mode and it says all of the hardware passes testing, but when it gets to the sound test where it goes through each sound in the game, it plays all of the sound effects except for the voices there, as well.

Any help would be appreciated.
 
Last edited:
Hmmm...

First thing to check would be the op amps that mix the sounds.

Do you have an oscilloscope, audio probe, or a logic probe that has audio?
 
No, I don't, but if you want to make a recommendation for a purchase for one of those, I'm open to suggestions. I would need to be walked through on what to check, though.

Also, just because, I pulled the rom that supposedly has the speech data and it has the same checksum as what mame is looking for, and the voices work when emulated with the rom from my board.
 
Alright, I've got one of those on the way now. I'm looking at the pcb and I'm not quite sure where the sound chip is. I took a couple pictures of the top board (doesn't look like the bottom one has any CPU's as far as I can tell, and since stereo out is on the top board as well) in case you don't mind pointing out where I need to be looking. I really appreciate your help!

The top left of the board has the left and right volume pots(?) and also the stereo connector CN5 which is to the right of those and is close to the edge.
http://img229.imageshack.us/img229/8089/img0664p.jpg
http://img87.imageshack.us/img87/8901/img0665m.jpg
 
VLM5030

You'll have to figure out what pin the output is on.

Soooooo...

Look up Lifeforce on MAWS: http://maws.mameworld.info/maws

Read the audio chips and you'll see the VLM5030 listed. Click on it and it'll bring up a list of other games that use it. Find a schematic of one of those games and you'll have the pin you need to check.

Find manuals here: http://pdf.textfiles.com/manuals/ARCADE/

Look up the manual for Punch Out and look at the schematic and you'll find that Pin 36 is the audio output pin.
 
Back
Top Bottom