Little problem on consolized MV 1FZ and suggestion for all

Hi I've just consolized a MV 1FZ, I've modified board to have stereo sound like Jeff Kurtz esplaned into his doc, and it works, just audio level is bit low.
Come to problem, my system works very well but just when it is just switched on and for first 30 mins I see thiny horizontal bars move fast on screen, like a noise into pic, is possible to see clearly this into cross test. About 30 min then system is on this problem disappares and images are perfects.
I'm using a PC power supply and have connected 5v and 12v on board. The power supply is capable about 20 A on 5v line, so should be ok. Also when those horizontal thiny bars are on screen, all works ok and system has no other problems. I wish to know if this can be a board problem or power supply problem, I've try to add an electrolitic capacitor on 5v line (4700 mf 25v) but nothing changes.

P.S. I suggest to all ppl has a MV 1FZ consolized connected via RGB to plasma or lcd tv to add 3 resistors (I've used 50 ohm resistors) between R-G-B pins and ground, this will reduce RGB signal that is too high for new tv so without those resistors, RGB signal overloads analogic/digital converter inside tv, when this happens alot of bright colors are lost into pic.
Other thing, if you can, connect "service button" on an unused button on your controller, so you can enter into service mode without set to on the first dip switch on board, I've done it and works well.

The audio level might be improved by a cap kit on the audio works. I'll let my betters speculate on the rest.

Its due to the audio mixer circuit you built. While that small circuit works, audio levels are very low.

You need to use the one designed by MKL.

I can't find his original post here @ neo-geo.com, however you can find another copy here at this site:

http://www.mcpat.com/2011/06/stereo-mod-neogeo-mv-1b-motherboard.html

Towards the bottom you will see the circuit. It obviously uses more parts, but it works far better with louder, cleaner audio. I have used the same circuit on a MV1B and it works much, much better than Jeff's circuit.

Thanks for audio circuit, broken. Any suggestion for thiny horizontal bars issue?

My first guess for that kind of stuff is usually power supply related.

The audio on mine (built by Jeff) is really low too, but it's extremely clean so I just turn the sound system up more.

OldTony said:

P.S. I suggest to all ppl has a MV 1FZ consolized connected via RGB to plasma or lcd tv to add 3 resistors (I've used 50 ohm resistors) between R-G-B pins and ground, this will reduce RGB signal that is too high for new tv so without those resistors, RGB signal overloads analogic/digital converter inside tv, when this happens alot of bright colors are lost into pic.

Click to expand...

Why would you suggest a 125ohm load on the RGB lines instead of applying the resistors inline?

I think is the same, but on my tv 50 ohm resistor is perfect, I've Panasonic plasma tv.

broken said:

Its due to the audio mixer circuit you built. While that small circuit works, audio levels are very low.

You need to use the one designed by MKL.

I can't find his original post here @ neo-geo.com, however you can find another copy here at this site:

http://www.mcpat.com/2011/06/stereo-mod-neogeo-mv-1b-motherboard.html

Towards the bottom you will see the circuit. It obviously uses more parts, but it works far better with louder, cleaner audio. I have used the same circuit on a MV1B and it works much, much better than Jeff's circuit.

Click to expand...

Thanks for the link on MKL circuit, i did the Jeff Kurtz Mod:





but idk why the sound started to having some garbage...
gona try this one, as soon i translated the thing.
thanks

The video bars could be inducted by the power supply or power wiring too near to the video signal. Simply twisting together pos & neg cables should help a bit, but the best is to shield the video wiring.

Hi dude,

OldTony said:

Come to problem, my system works very well but just when it is just switched on and for first 30 mins I see thiny horizontal bars move fast on screen, like a noise into pic, is possible to see clearly this into cross test. About 30 min then system is on this problem disappares and images are perfects.
I'm using a PC power supply and have connected 5v and 12v on board. The power supply is capable about 20 A on 5v line, so should be ok. Also when those horizontal thiny bars are on screen, all works ok and system has no other problems. I wish to know if this can be a board problem or power supply problem, I've try to add an electrolitic capacitor on 5v line (4700 mf 25v) but nothing changes.

P.S. I suggest to all ppl has a MV 1FZ consolized connected via RGB to plasma or lcd tv to add 3 resistors (I've used 50 ohm resistors) between R-G-B pins and ground, this will reduce RGB signal that is too high for new tv so without those resistors, RGB signal overloads analogic/digital converter inside tv, when this happens alot of bright colors are lost into pic.

Click to expand...

I have a question, have you put a resistor in the sync line aswell?? because your problem with the horizontal bars sounds like a sync issue, if you didn't put a resistor in the sync line try a 470 ohms resitor on it.

Saludos

No I don't, I'll try it today, ty.