Voltage adjust knob

Is the voltage adjust knob on a super neo 29 a specific color when the PSU is turned on. Mine is red when the PSU is powered. Does this mean my voltage is off. I have heard that when it is the correct voltage the light should be green. Is this true? Don't have a multimeter to check and my MOBO seems a little off when all 4 slots are in use.

Do yourself a favour and invest in a multimeter, essential equipment for this hobby - and they do not have to be expensive, probably pick one up for 10-20 bucks. Good insurance against fried board sets. Believe me.

Regarding the LED, usually red means powered on, it does not indicate correct/ incorrect voltage.

LED is red on my MVS.

I can also vouch for the Multimeter idea. Saved my skin and my hardware a few times!

Ya red is correct for an MVS. Not all PSUs have that green/red +5v adjust.

Picking up a multimeter today to check it. What should be the correct voltage going to a 4-slot MOBO? How do I check this? Fairly new to this shit and don't want to fry anything. Is their anything else to check while I'm at it besides the power to the board?

I don't think you need to adjust the voltage if you already played the cab with no problems BUT I do recommend getting a multimeter for future use.

I did play the cab for about an hour last night and on the last level of MS3 the screen went green and the MOBO seemed to reboot itself. I don't know if this is common since these machines and boards are not usually 100% reliable or my PSU is set to low and thats why? I have a multimeter now so how do I check to make sure?

lachlan said:

LED is red on my MVS.

I can also vouch for the Multimeter idea. Saved my skin and my hardware a few times!

Click to expand...

How did a multimeter save you from having a fried board. Did you just happen to check a board with a multimeter before it fried or did have attached to a board already?

Check the voltage at the jama/mvs edge connect, not the psu, as there will be voltage dropped in thre harness.

Just connected the multimeter to the jamma harness and only got a reading from
.01 to .03. This seems wrong. I was told that I should have the jamma harness connected to the board to measure. Will this change the reading. When I connect the jamma harness to the edge connector there is no room to see the connector. Do I place the pins from the multimeter on the backside of the harness. And does it matter if carts on in my slots or not? That seems like the only way to measure. I need help fast, anyone out here that can help now!

O.K, I think I figured it out. With the jamma harness connected to the MOBO I am reading only 4.6? This is too low I take it. i adjusted the voltage knob and am now reading 5.05 with 4 carts playing. Is this good or should it be higher or lower?

That's good but most people I have seen use 5.1v

Yes, just a whisker over 5 is fine. 4.6v may have caused intermittent problems like resetting or no boot up.
Your meter has already payed for itself

Thanks for all the help fellas!

Was able to set it as high as 5.07 but no higher. The voltage adjust knob will not turn anymore and appears to be maxed out. Is this normal or should I be able to adjust the voltage much higher? Not real worried since the cab is working now.

If you are worried about ability of power supply and may want to have it last longer, recommend you to do two things.

Running 4 cartridges at once sure consumpts a lot, but one is to check it's current ability first.

>Just check +5v at jamma connecter without any pcb hooked and see max. voltage.This will show max. ability of now.

>The other is to clean up power supply and remove all dusts. This usually revives few extra voltage to it, and makes it last longer.

If you gain some, then hook up pcb again and re-adjust it between 5.1 to 5.2 for 4 slot if possible. If can't, just set to max. it's normal aging wear of power unit, recommend you to replace it in the future when it shows only +5.0v max alone.

These tips are nothing special, very fundamental check and step you'll have to take to know and to keep it's condition. Remember, also need to check and readjust every voltages, every time u swap to different pcb. Every time. Many here does this, but if any who didn't know, should remember and make it a habit too, even though it's kinda trouble some. Every pcbs has and works with different "good" voltages.