Maple
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Australia

I've decided to just not add the Half Speed crystal oscillator (in the near future anyway) because I don't have a changeover switch right now and it was the least needed/wanted feature (since I have a potentiometer). So anyway, The potentiometer switch functions correctly now. BUT. Now there is NO SOUND whatsoever! All I get is static that changes pitch with the potentiometer, and where there's meant to be sound on a game, I get infrequent little static surges through the earphones. What did I do? What could be the problem? hmm Aside from this, all that's left is fixing the prosound mod, and then soldering the 2 wires coming out of the previously installed backlight. I guess it does pay off to have some half finished mods tongue

Further prosound info: I'm pretty sure there are no solder bridges. You see, the reason I think I may have accidentally severed one of the leads is because I was scraping around with a small sharp blade to get rid of any potential solder bridges... Also, I guess first thing is to get some sound working, but with the left earphone lead, I was thinking it may be easy to just solder an extension wire from that point to another part of the board. As I said before, the copper gets in the way so its hard to see where the leads go, but one way I could find out is if I knew what each of the 4 wires going down to the stock audio jack individually do. Does anyone know? This way I can trace them back on the board. Of course, I don't know if this would work but it's worth a try until I do know.

Last edited by Maple (Aug 8, 2011 3:02 pm)

kineticturtle
Offline
Matthew Joseph Payne

From the side with the white wire, they are switch normal, ground, right output, left output.

from http://lowgain-audio.com/GBclassicmod.htm - probably also helpful to you smile

Signal is already headphone-amped at that point though.

Regardless, I disagree with your assertion that the pitch mod works. If these weird glitchy sound things only happen when the pitch mod is on, then clearly something is wrong with the pitch mod.

Maple
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Australia

Thanks again, and, no no, the glitchy sound surges happen REGARDLESS of weather the pitch mod is on or not. It's just, when the pitch mod IS on, the frequency of the general static changes. So it's all static either way, otherwise it would be obvious that it is the pitch mod at fault. So I'm still kinda lost with that... (Unless you still disagree? I'll try desoldering the 3 points on the board and see if there's sound.)

Maple
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Australia

Everything is wired up. Still no sound. sigh. Could I have destroyed only the sound part by static?

2PLAYER
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Rhode Island

Does anything happen (sound/volume wise) when you turn the volume knob?

kineticturtle
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Matthew Joseph Payne

Screen looks normal when the gameboy is running at normal speed? How much heat have you been applying?

Maple
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Australia

@2PLAYER: The only thing is there appears to be (not visually, I mean audio-wise) lots of static when it's turned all the way downwards (as in turning it towards you if you were to hold it normally. I can't remember if this is volume up or down).

@kineticturtle: Yep, and, um, the iron is 30w, and sometimes I hold it there for a bit... It makes sense that this could have damaged the parts around there at the 3 points you're required to solder to for the prosound mod. I held it there for a bit on other hard-to-solder parts too, but that didn't seem to affect anything...

Last edited by Maple (Aug 9, 2011 3:58 am)

kineticturtle
Offline
Matthew Joseph Payne

Are you keeping your iron tinned? I'm just speculating without actually seeing you work, but if the iron isn't tinned and it isn't reacting quickly enough, you could be putting a lot of extra heat into the CPU, that could potentially do this.

Speculation is relevant here though, as I've seen and heard a lot of broken game boys, and this is a new symptom to me. Maybe nitro or rolf or someone has input to offer.

Krubbz
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Fargo

Don't give up, cuz I'd like to learn how to switch between crystals as well!

Maple
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Australia

Everything is wired up. Everything works except sound... Which is the main reason I have for modding it. I want to compose music.

@kineticturtle: I keep the iron tinned but it just doesn't seem to react as well as in videos I've seen, so I have been applying too much heat, it seems. I hope this is fixable without getting a new Game Boy.

@Krubbz: I decided to not do that all together, because I didn't have an ON-ON switch. I only have ON-OFF switches. But, I have an untested theory that maybe the crystal oscillators need to have electricity going through them in the right direction for them to work. Of course, I know nothing about electronics, but yeah.

If anyone can further help me, I do highly appreciate it smile Hopefully I can get this working properly once and for all. It's slightly discouraging!...

Apeshit
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Maple wrote:

@Krubbz: I decided to not do that all together, because I didn't have an ON-ON switch. I only have ON-OFF switches. But, I have an untested theory that maybe the crystal oscillators need to have electricity going through them in the right direction for them to work.

These kind of crystals aren't polarized, so that's not the problem.

Might have been answered already but:

is it the non ground wire that goes through an ON-OFF switch?

Either wire can go to the switch. Generally the anode, though.