MAK Strike supergun no sound

[slk486]

This is driving me crazy.

Very recently got a MAK Strike supergun from ArcadeForge.
http://wp1114205.wp150.webpack.hosteuro ... ucts_id=16"
I wanted to be able to turn off the standard jamma mono pins, so a wire was soldered to jamma pin 10 and jamma pin L, so I connect those to the stereo terminals on a need basis (l for mono, r for gnd).

None of my original pcb's have any sound when connected. Game plays fine.
Tried everything I could think of (with help from ArcadeForge)

Measured connections with multimeter: jamma pin 10 (audio left) connects to scart audio left, and mono jack center, jamma pin L (audio gnd) connects to universal MAK gnd.
Tried another scart cable where sound is known to work
Tried connecting a mini stereo to the mono jack.
Tried connecting jamma pin L to scart audio right, since that is what ArcadeForge tells me their standard MAK Strike uses.
Made sure the 5v line had ~5.0 at the jamma edge with a pcb connected.

What I havent tried:
Cranking up the 5v further
Find a place on the pcb to measure 5v and adjust psu so there's 5.0 at that point.


No sound, at all.

Then today I receive a humongous boot of r-type (3 layered pcb's), that needed 5.6v to display all the graphics correctly.
Sound works on this board, but no controls (this is probably another issue?).


Any tips?

[Korszca]

Why is Pin L wired to ground? Pin L is Speaker- not ground. If you're wiring it to a RCA phono jack, you'd wire Pin 10 (Speaker+) to the center pin and take any of the real grounds and wire it to the ground post.
Also, most (if not all) games don't use 5v for sound. They use either 12v or -5v. Perhaps you have a lot of games that use -5v for sound but no -5v from your PSU? Sounds like that R-Type boot may use 12v for sound which is why you hear it.

[slk486]

I don't know why it's wired to ground - that's just the way that particular supergun is wired.

My jamma extender doesn't have -5v wired, so since sound worked with my old supergun, that also can't be the issue.
Maybe I should recheck the 12v line, if that's what most boards use for audio.

The games I've tried are: Thunder cross, NewZealand Story, Fire Shark, and Daioh.

[Korszca]

I'd remove the ground from Pin L, that's an incorrect place to wire ground and may cause problems. Then check your 12v. All those boards run sound from 12v.

[slk486]

I'd remove the ground from Pin L, that's an incorrect place to wire ground and may cause problems. Then check your 12v. All those boards run sound from 12v.

I wish I could, but it's connected to ground somewhere inside the supergun pcb.

[Korszca]

Just cut the trace.

[slk486]

Can't see any traces for ground

[Korszca]

Is it at all possible for you to return it and buy a real supergun? That may well be your best bet if adjusting the 12v doesn't work.

[slk486]

I hope so, if that is the issue. What is a real supergun for TV use, if the MAK Strike isn't?

[Korszca]

Anything with proper wiring. Even a Vogatek would work well, provided you have a spare ATX PSU. I think it's the MK V that has the DA-15 ports for Neo-Geo sticks and SCART like that MAK one you have. The only downside is that you'd have to get a pair of passive speakers for the Vogatek unless you're OK with passing speaker level audio to your TV (almost always OK as long as you turn the volume on the PCBs all the way down). In fact, it doesn't look like the MAK one you have attenuates the audio so you'd be doing that either way.

Still, check and adjust the 12v first. Better to only have to make the easy fix whenever possible.

[slk486]

I just don't get, why it would have improper wiring in the first place... It's a jamma supergun. How can it not work for standard jamma PCBs...

All I can do wit the 12v is check it. No way to adjust it (or does the 12v adjust together with the 5v if I tweak the pot on the psu?). So either way I'd be effed.

[Korszca]

Because people think they can "enhance" a standard. Like there isn't any reason it's a standard.
I shot them an email asking them to explain their design decisions regarding the audio output.

The 12v will generally change when you adjust the 5v but there is most likely a pot inside the PSU for adjusting the 12v. I can understand if you're not wanting to crack open the PSU to adjust 12v though.

It's also possible that the PSU doesn't output enough amps on the 12v.

[slk486]

Well I've been constantly hammering them for support since I hooked it up for the first time (and have received suggestions), so he is well aware of the issues I have and have also asked him why speaker- is grounded, with no way to disconnect.

Last time I measured the 12v it was spot on, but I'll go check it again now.

Edit: 11.85, with +5v at 5.01. Acceptable?

[Korszca]

The only other thing I can think of doing is connecting one of these to the mono audio RCA out:
http://www.computercablestore.com/5_FT_ ... ID459.aspx"

Since making JAMMA "stereo" is just doubling the mono to both channels (fake stereo), and then hooking it up to the L and R jacks of your TV. That's slightly different than connecting a mini stereo to the mono jack, and (maybe) worth a shot.

Edit: 11.85, with +5v at 5.01. Acceptable?

Yes, or rather, should be. How many amps are you getting off the 12v?

[slk486]

The only other thing I can think of doing is connecting one of these to the mono audio RCA out:
http://www.computercablestore.com/5_FT_ ... ID459.aspx"

Since making JAMMA "stereo" is just doubling the mono to both channels (fake stereo), and then hooking it up to the L and R jacks of your TV. That's slightly different than connecting a mini stereo to the mono jack, and (maybe) worth a shot.

Have already tried connecting a mini stereo system to the mono jack. If the problem is from the gounded speaker -, then it would be the pcb's having an issue with it, since only connecting the speaker+ to the scart audio left, still gives no sound.

Edit: 11.85, with +5v at 5.01. Acceptable?

Yes, or rather, should be. How many amps are you getting off the 12v?

Don't know how many amps, but that was measured with no pcb on, so it would likely drop. Will check again.

Edit: 9.65 with a pcb connected. Still acceptable after pcb power draw?

[Korszca]

Edit: 9.65 with a pcb connected. Still acceptable after pcb power draw?

Absolutely not. It should be 12v (+/- 10% or so) with the PCB connected. The PSU should be marked with the amperage on it. Something like 5v @ 15A, 12v @ 2A.

[rolins]

The only other thing I can think of doing is connecting one of these to the mono audio RCA out:
http://www.computercablestore.com/5_FT_ ... ID459.aspx"

Since making JAMMA "stereo" is just doubling the mono to both channels (fake stereo), and then hooking it up to the L and R jacks of your TV. That's slightly different than connecting a mini stereo to the mono jack, and (maybe) worth a shot.

Have already tried connecting a mini stereo system to the mono jack. If the problem is from the gounded speaker -, then it would be the pcb's having an issue with it, since only connecting the speaker+ to the scart audio left, still gives no sound.

Edit: 11.85, with +5v at 5.01. Acceptable?

Yes, or rather, should be. How many amps are you getting off the 12v?

Don't know how many amps, but that was measured with no pcb on, so it would likely drop. Will check again.

Edit: 9.65 with a pcb connected. Still acceptable after pcb power draw?

Thats very low. What game are you playing that gives 9.65v?

I also bought this supergun and I wasn't getting any sound through the scart connector either. Sound is fine through the phono jack with my MP3 speakers using a headphone jack to phono plug, but why not through scart? Didn't make any sense to me when I was testing my boards.

I had mine connected directly to my scart modded XRGB-2, and pins 2 and 6 are connected for audio input only. The difference is on the Mak Strike's scart connector, its audio is on pins 1 and 3. I've talked to the builder and apparently European TVs swap audio pins internally (I guess) that why it works for some. Well my XRGB-2 doesn't swap those audio pins so I wasn't getting any sound.

What I did was look underneath the Mak Strike, and cut the traces from Audio_L and Audio_R terminals leading to the scart pins 1 and 3. Then solder a jumper wire from Jamma_10 to scart pins 2 and 6. After that I got sound through scart.

I don't suggest doing what I mentioned, because it sounds like you power supply be the culprit.

[slk486]

This was on NewZealand Story. I must've chosen a bad place to measure (or haven't had full contact), because today I get 12.75 after tweaking the +5v to 5.0 with that pcb connected.
I don't have sound through the phono jack either.

[slk486]

Ok, by advice of ArcadeForge I lifted Pin L, so it was not grounded anymore, and sound now works!

Somewhat... Sound is played, but is very distorted / strained. Like when an mp3 player is running out of batteries.
Power issue? +5v is 5.0'ish, 12v is 12.5'ish. I'm afraid I'll hurt the boards if I just turn up the +5v.

If I turn the poti on the pcb down very low, the distortion is almost gone - but sound is very very low
Turning up the +5v (to get the 12v up) alleviates the distortion somewhat, but running at 5.56 with very hot chips isn't recommended is it?

Help appreciated

[Korszca]

Ok, by advice of ArcadeForge I lifted Pin L, so it was not grounded anymore, and sound now works!

Pretty sure I was the one who told you to get rid of the ground on Pin L

Somewhat... Sound is played, but is very distorted / strained. Like when an mp3 player is running out of batteries.
Power issue? +5v is 5.0'ish, 12v is 12.5'ish. I'm afraid I'll hurt the boards if I just turn up the +5v.

If I turn the poti on the pcb down very low, the distortion is almost gone - but sound is very very low
Turning up the +5v (to get the 12v up) alleviates the distortion somewhat, but running at 5.56 with very hot chips isn't recommended is it?

Help appreciated

Keep the 5v at 5v. 12v is well within good range. What speakers are you using?