Yes that reminds me where I got the YM3012 from. Okay So I've got my YM3012 mixed with the LM324 in my previous post sorry for confusion. So no voice, I would start at the LM324 (not YM3012) next to the VLM5030. Hopefully that custom VLM5030 isn't an on board voice synthesiser and dac all in one.
Sorry had to edit this as i was getting the VLM5030 mixed up with the 007420 (insert facepalm emote here). Hard to explain what I am thinking sometimes but bare with me
as it's working sometimes, you may want to start with the crystal for the vioce/sample chip
Do you know which ones specifically? what would be the cheapest option to get some. Can't find any on ebay.I may be wrong, but if memory serves me correct, I believe that the VLM5030 chip can be sourced relatively cheaply if need be. Because it was used by Konami as an enhancement chip on a few of their bigger Famicom cartridge game releases.
According to mame source both YM2151 and VLM5030 uses the same clock signals so that can be ruled out. Besides he doesn't have a scope anyway. But definitely a valid point though and still worth checking in case the signal is being messed up along the way.as it's working sometimes, you may want to start with the crystal for the vioce/sample chip
Sorry I was just going by the source code. There's two cyrstals in there with the other one being 24mhz according to mame source. imo would be silly to use clock dividers on the 24mhz when you can just use the same one for the sound. The 24mhz signal is used by the two CPUS I think. So just an assumption i've made. Are there pinouts for VLM5030 at all? Always a good idea to check clocks regardless though. I feel like a twat for just not digging out my own pcb myself to be honest. But its not as easy as it seems.if the voice chip uses the crystal and the other sound chips use a different clock source then it can be the issue
it could just need resoldering.
if you ever open a crystal, inside the can is a glass disk with thin wires connecting it to the can base - those wires and the glass can all fail
…although categorised as similar hardware, the layout is completely different to other games in that category.