Powering a Neo Geo help two power supplies?

seanengadet

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Hey all
My new to me 4 slot is a bit of a pig and needs 5.41 volts to run. I can't figure out why. Anything less and I get graphical glitches and lockups. Issue is my 12v running the audio is then ~15v. I worry that'll damage the ha13001 amp over time.

So my question is should I run the 12v form a second supply, and if so can I wire both to the same 110 input daisy chained?

Should I build a voltage regulator with a 7812 or something instead? Or is it safe for the amp to run with that input?
 
Hey all
My new to me 4 slot is a bit of a pig and needs 5.41 volts to run. I can't figure out why. Anything less and I get graphical glitches and lockups. Issue is my 12v running the audio is then ~15v. I worry that'll damage the ha13001 amp over time.

So my question is should I run the 12v form a second supply, and if so can I wire both to the same 110 input daisy chained?

Should I build a voltage regulator with a 7812 or something instead? Or is it safe for the amp to run with that input?

Where are you testing the voltage at? I found testing +5v on the back of the credit LED pcb is easiest and works pretty good. I may take a pic if it helps.

Just my experience, some bootleg carts are power hogs and prevent the other slots from working. If you have all genuine carts, you shouldn't have any problem running all 4 slots at normal +5 voltage.

If the chips on the +5v rail are seeing > 5.25v I don't think they will last long. Most chip ranges state +/- 5% tolerance with the -5v rail having more tolerance than others.

Voltage Rail Tolerance Minimum Voltage Maximum Voltage
+3.3VDC ± 5% +3.135 VDC +3.465 VDC
+5VDC ± 5% +4.750 VDC +5.250 VDC
+5VSB ± 5% +4.750 VDC +5.250 VDC
-5VDC (if used) ± 10% -4.500 VDC -5.500 VDC
+12VDC ± 5% +11.400 VDC +12.600 VDC
-12VDC ± 10% -10.800 VDC - 13.200 VDC
 
Where are you testing the voltage at? I found testing +5v on the back of the credit LED pcb is easiest and works pretty good. I may take a pic if it helps.

Just my experience, some bootleg carts are power hogs and prevent the other slots from working. If you have all genuine carts, you shouldn't have any problem running all 4 slots at normal +5 voltage.

If the chips on the +5v rail are seeing > 5.25v I don't think they will last long. Most chip ranges state +/- 5% tolerance with the -5v rail having more tolerance than others.

Voltage Rail Tolerance Minimum Voltage Maximum Voltage
+3.3VDC ± 5% +3.135 VDC +3.465 VDC
+5VDC ± 5% +4.750 VDC +5.250 VDC
+5VSB ± 5% +4.750 VDC +5.250 VDC
-5VDC (if used) ± 10% -4.500 VDC -5.500 VDC
+12VDC ± 5% +11.400 VDC +12.600 VDC
-12VDC ± 10% -10.800 VDC - 13.200 VDC

Yeah, this is measured on the edge AND at JP1. At 5.01 the game doesn't even boot, at 5.1 - 5.2 it locks up constantly. The behaviour is the same with one or all four games in and they're all legit carts.
 
Yeah, this is measured on the edge AND at JP1. At 5.01 the game doesn't even boot, at 5.1 - 5.2 it locks up constantly. The behaviour is the same with one or all four games in and they're all legit carts.

Just for completeness, I test and set my voltage by measuring at locations shown in pic.

I guess I can't offer great next step advice for you then. Just seems like something else is going on. What kind of power supply is in there now and have your tried a new or different one? I would do that before trying to rig up a separate power supply for 12v.
 

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Just for completeness, I test and set my voltage by measuring at locations shown in pic.

I guess I can't offer great next step advice for you then. Just seems like something else is going on. What kind of power supply is in there now and have your tried a new or different one? I would do that before trying to rig up a separate power supply for 12v.

Power supply seems well behaved for sure. Game has not been back in it since I fixed the amp. Maybe magic will happen!
 
clean your edge connector.

I had to wash all the 4 slot boards and cartridges with simple green at work to get everything to work reliably.
 
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