AES POWER ISSUE WITH NEO AES SD

BIG BEAR

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I trace repaired an NEO-AES(1st generation model,no daughter board) a little while ago and everything was working but I had to fiddle around with the cartridges too much to get them functioning properly so I replaced the cartridge slots(waited a couple of weeks from ali babba) and everything I throw at it works perfectly including MVS-AES converter with the exception of the NEO AES SD which only works on random power ups or when I press on certain areas around the work ram pathway.WITHOUT the SD card inserted into the side of the NEO AES SD it works fine on every power up.

My thinking is that there is a voltage issue affecting the work ram.
I've changed out the 5v barrel,the power transistor,a resistor and a couple of capacitors along the voltage pathway,power switch,the 68k(now added a socket),the B0 chip,work ram,video ram,a couple of Ls05's,Hc259,some HCT chips associated with the work ram & B0 chips only to have it yield the same results.

Any ideas would be appreciated...
Again Everything works that I throw at it with the exception being that SD card inserted into the NEO AES SD.The voltage drops under 4.8 and the unit just hangs like it would on any aes not getting enough power to boot the game and the reset button will not respond forcing me to power it off.
This is just a problem specific to this particular system. I have another AES,same model that works fine with and without the SD card inserted into the NEO AES SD.
BB
 
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Neo Alec

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It really sounds like that console is just fine and doesn't happen to work well with the Neo SD. How many AC adapters have you tried? I feel like one outputting a slightly higher voltage would get it working.
 

Niko

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Are you using the original AC adapter?

Terraonion mentioned that alot of people have problems with 3rd party AC adapters because they produce alot of noise which the NeoSD is sensitive to.
 

BIG BEAR

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Forgot to mention that I've used several adapters as well... Original and 3rd party..

BB
 

daskrabs

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Do you have a meter that measures amperage? Check the draw on the PSU with the SD card at the cart slot, then compare that to your AES that works. I'm guessing your PSU is 5V 3A, so maybe this unit needs 4A if it's maxing out the draw. Only other idea is that the design of the early AES units prevents the required current from being drawn by the NeoSD.
 

thegreathopper

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Hi Big Bear, I also have a 1st gen machine and have run two different NeoSD carts with no problems at all, not sure if that info helps, my serial number is very low I can add it later.
 

RAZO

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Don't know if this is going to help any since you say your NeoSd does work without the NeoSd card inserted. One of my Neo's (U.S Gold System) was having the dreaded scaling issue with the NeoSd but ran fine with original carts. It was just that specific console that was having a issue.

The New firmware update 1.07 that hasn't been released yet fixed the issue. You might want to give that a try. Contact Todd and see if he could hook you up.
 

Heinz

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If it truly is a power issue I wonder if supplying the AES with an arcade or desktop power supply with adjustment would help ascertain whether the AC adapters aren't up to the task?
 

Atro

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Do you have a meter that measures amperage? Check the draw on the PSU with the SD card at the cart slot, then compare that to your AES that works. I'm guessing your PSU is 5V 3A, so maybe this unit needs 4A if it's maxing out the draw. Only other idea is that the design of the early AES units prevents the required current from being drawn by the NeoSD.

If it truly is a power issue I wonder if supplying the AES with an arcade or desktop power supply with adjustment would help ascertain whether the AC adapters aren't up to the task?

What they said.

This cart looks no different than "everdrives", which are authentic power hungry bastards. Since it's a 1st gen console, I'd feed it +5v from an arcade PSU which has a lot of AMPs to deliver. If that doesn't solve the issue, I wonder what will...
 

BIG BEAR

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I appreciate all of the replies thus far. I just want to make clear that I own an exact model(NEO-AES) as the one I repaired and the NEO AES SD powers up fine every time with mini sd card inserted. With the repaired system, the voltage runs through the system fine until I plug that SD mini card into the side of NEO AES SD and then the voltage just drops to like 4.7X rather than giving me 4.8X with cartridges inserted.
It would seem it's an AC adapter issue but my AES proves that theory incorrect.
BB
 

Bratwurst

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My most immediate suggestion is to replace all the other capacitors, maybe something is out of spec enough that it can't keep up and is parasitically pulling off the main rail. Probably not a dead ringer solution but it at least is something to easily rule out.
 

thegreathopper

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You mentioned you repaired some traces, I wonder if what you repaired them with ie cable is too small and causing your volt drop. I would try doubling up your trace repairs or use a cable with a larger conductor.
 

GadgetUK

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I wonder if theres a cap with high ESR there? Maybe try some deoxit in the power switch too!
 
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