Really Annoying Problem

Hi,

My recently consolized MV-1C is working great except for one minor, but very annoying problem.

Before I start, I have hooked up the audio to go through the SCART cable into the TV.

Anyway, the problem is that there seem to be some banding going on the screen in relationship to the sound, as if there is some signal disturbance going on. Basically, the more I crank up the volume screw on the motherboard the more banding I get on the screen. If there is nothing playing (audio) the banding goes away. I have sort of solved this problem by putting the sound low on the motherboard and high on the TV, but as expected one can hear a hum in the background. Anyone got any idea where things might have gone wrong?

Another thing... is it harmful to the TV set to pass the MV-1C sound through SCART, even though its kept at a low volume?

Thanks!

<small>[ August 07, 2003, 06:37 PM: Message edited by: Nostromo ]</small>

I see a lot of people connecting the JAMMA audio output to TVs and stereo equipment, and you should never ever do this. It's bad, and you'll overheat (and possibly fry) your JAMMA PCB and possibly damage the receiving equipment.

You may also get interference on the screen or in your audio.

Ok, I have now hooked up the audio to a seperate speaker and the banding is gone.

Thanks!

NEOGEOman:
I see a lot of people connecting the JAMMA audio output to TVs and stereo equipment, and you should never ever do this. It's bad, and you'll overheat (and possibly fry) your JAMMA PCB and possibly damage the receiving equipment.

You may also get interference on the screen or in your audio.

Click to expand...

Is this also true if the MVS goes through a Supergun and then to the tv?

Is this also true if the MVS goes through a Supergun and then to the tv?

Click to expand...

Since every 'supergun' is different, there's no way I can answer this question. If your supergun does nothing to the audio then yes, it's still bad. Car audio shops sell a speaker-level to line-level convertor for just this purpose.

If you're not using one, and if you your PCB doesn't have headphone or line connectors, then I suggest you touch your audio amp heatsink on the PCB one day while playing. Chances are it's HOT. During proper play (ie connected to a speaker) it will barely warm above room temperature.

yuo just used audio gnd on the jamma connector right? just cut the audio gnd and use gnd from pin 1 or 2 and the same at video gnd and the bad picture should be gone or just turn down(a bit) the volume on the mvs and turn sound on tv a bit louder

NeoGeoMan.... if i put a resistor on the Audio out to bring down the voltage to an acceptable level, would it be ok if I hook it into the TV via scart? In that case, what sort of resistor would I need?

Thanks!

Pocket Man:
yuo just used audio gnd on the jamma connector right? just cut the audio gnd and use gnd from pin 1 or 2 and the same at video gnd and the bad picture should be gone or just turn down(a bit) the volume on the mvs and turn sound on tv a bit louder

Click to expand...

I did turn down the volume on the MVS and turn sound louder, but like that I`ll get a lot of hum.

NEOGEOman:

Is this also true if the MVS goes through a Supergun and then to the tv?

Click to expand...

Since every 'supergun' is different, there's no way I can answer this question. If your supergun does nothing to the audio then yes, it's still bad. Car audio shops sell a speaker-level to line-level convertor for just this purpose.

If you're not using one, and if you your PCB doesn't have headphone or line connectors, then I suggest you touch your audio amp heatsink on the PCB one day while playing. Chances are it's HOT. During proper play (ie connected to a speaker) it will barely warm above room temperature.

Click to expand...

My Supergun send sthe sound through Scart to the TV. I can alter the level of sound with the speaker slider on my MV-1F. Does that help in answering my question?

Is there anything I can check inside my Supergun to see if the sound is altered by it? BTW the Gun is a professionally built one so I hope the sound has been 'fixed'.