How many amps on the Peter Chou +12?

modessitt

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Anyone know? I was going to tap into the +12 on my bench PS to power a small amplifier board that can take 6-15vdc, but it says "500mA max", and I don't want to blow it up...
 
AFAIK there are a number of different PS units identified as "Peter Chou", with different specs.

However, 1/2A at 12V is 6W, which is plenty loud. Assuming it's an audio amp you're talking about, keep the volume moderate and it shouldn't pull too enough current to be an issue.

EDIT: Wait a sec... is it the Peter Chou the says 500mA max, or the amp board?
 
The PS is one of BobRob 15A switchers. The audio amp says 500ma max. It's a 3A mono, so I should be fine. Just wanted to be sure.

Building a "cheap" ($20) audio probe/bench amp for diagnosing audio circuits and bench-testing PCB's that don't have amplifiers on-board (like Centipede, Donkey Kong, etc)...
 
Mod? Seriously?

OK... 500ma max is the current draw for the amplifier... you can hook it up to whatever you want that puts out 500ma or greater. It's not going to draw any more than it needs... but if something shorts out you'll want a 3/4A fuse to keep things from smoking too much.

Think about it this way... your car battery can put out hundreds of amps of current into the starter to crank the engine. Your car stereo has a 5 to 10A fuse... it's not pulling hundreds of amps or getting pushed hundreds of amps... it's only pulling what it needs unless there's a catastrophic short circuit somewhere and that's what the fuse's job is for.

RJ
 
Yeah, it works! Just bench-tested a DK board on the bench and got perfect sound through my bench speaker. Going to rig up something for probing an audio ciircuit and try that next.

If anyone would like a write-up on how to do this (using a kit from Radio Shack of all places), let me know and I'll create a separate thread for it...
 
Please do. Anything that helps others is a good thing to do.
 
Okay, the audio probe works, too! :)

Of course, I just killed a board. I still had hum on the input and saw a solder blob on some pins of a big square surface-mount chip. Shut it off, got out the solder braid, removed the blob, still had the hum, noticed a couple legs where the blob was looked like they might be touching, tried to gently separate them with a small-tip razor pencil - and the damn leg busted off the damn chip flush with the body so there's nothing to attach a jumper to. :mad: And of course the game doesn't work now.

Can't find ANYTHING on the chip (SPR800E), and don't have the tools for removing the chip and installiing a new one. Guess I'm going to have to pony up some bucks for a new board since this isn't mine.... :001_scry:
 
Solderbraid is nasty stuff especially on surface mount chips, the solder always locks on at the wrong time and its easy to rip legs clean off. All is not lost tho, you can file the surface of the chip back to get to the legs as they head inwards. I did it here...

http://retrocomputermuseum.co.uk/forum/index.php?topic=3601.0

DSCN7683.jpg


DSCN7691.jpg


... it would be fairly easy to do if it jthe lost leg was on a corner, more filing to do if it was in the middle.
 
It is a corner leg, so I might try that. My other problem is that the damn pad pulled up and the trace apparently goes under the chip to a via, so I'd then have to figure out where to run the damn jumper.

If I could get a pinout of this chip to see if it's ground or something obvious, then I could just run the jumper to where I needed it...
 
Customs would not have any datasheets you can find, the best you could do is find a schematic of the game, or a board from the same era and manufacturer that uses the same customs and see how the pins are labelled.

Just a mini hand file, dremel is an option but it might be easy to dig too deep too quickly and cut the tracks again.
 
Customs would not have any datasheets you can find, the best you could do is find a schematic of the game, or a board from the same era and manufacturer that uses the same customs and see how the pins are labelled.

Just a mini hand file, dremel is an option but it might be easy to dig too deep too quickly and cut the tracks again.

Maybe I'll use a dremel to get started and go down about halfway, then use the hand file...
 
Use a grinding stone on the dremel... works very well. :)
 
Use a grinding stone on the dremel... works very well. :)

You want to fix this for me? Even if I get to the pin, I won't know where to connect it to. If you can pull the chip and find the trace, that would do it. Maybe you could fix the hum too.

Either spend money with you or spend money buying a new board...
 
Honestly? I cringe at repairing boards with repair damage.
 
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