Blew up the 24V on my PP7B during testing, so I made a test aid!!!

timberterror

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Blew up the 24V on my PP7B during testing, so I made a test aid!!!

I've had a couple spare Nintendo PP7B power supplies lying around and decided I would recap one of them and put in in my Junior. I ordered the caps from Mouser a couple months ago and forgot about it.

Today I decided to do it. The capping was no problem and it went back together fine. I hooked it up to a Nintendo isolator and began to check voltages. As I was testing the +24 volts my probe slipped and shorted the +24 to the -5. I heard a pop, a little burning smell and no +24 volts. I pulled it apart and checked the fuse and it was good. I could smell, but not see any damage. Put it back together and no +24volts. Trying to test voltages on those small connectors is a royal pain.

Since I've been helping Dokert build the Atari test aids, I thought I'll build a test aid for my PP7B. I picked up a couple parts from Dokert and built it. Since I have a PP7A power supply as well I made it to test both.

On the one end it plugs into the power supply and on the other easy to use plugs for a multimeter. I made the cables 5ft long per Dave's suggestion so it would be easy to test in cab as well as on the bench.

I may have killed a power supply, but I gained a nice test aid...... - Barry
 

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I wonder how easy it would be to build a rig to test the power supply under load. You already have cables built. A small PCB with correctly valued resistors ( I cannot remember how to calculate that) on it would help. Just plug it in and it would draw the same current from each voltages supply that a normal game PCB would. That way a Power Supply could be tested for any length of time with no danger to a game PCB. Test points for each voltage could be easily set up. To make it really neat, analog to digital converters along with 7 segment decoders and 7 segment LEDs could be added to give an exact voltage reading without the need for a meter. Esssentially, it would be built into the PCB itself.

Maybe I am just rambling here but it sounds like something like that could be really useful for PS testing. It could be set up for regular switchers or even linear supplies with some connector mods. I know there are at least a couple of guys on here with the know how for something like that. I also know that I am not one of them but there might be some market potential in the idea.
 
I wonder how easy it would be to build a rig to test the power supply under load.

It is not as easy as you make it sound.

I built a true load tester for the Atari Test Aid +5vdc section, and damn did it get hot.

Now, Bit Slicer made a very nice load tester for A/R's.
 
Looks nice. Where did you get the little black connectors to plug into the power supply headers?

Edward
 
All I can say is......Sweeeeeeeet. I've been there, and done that with a slip of the probe on these power supplies. If you happen to make more, I'd be interested in one. Of course my interest was truely peaked since you set it up to do PP-7A's.

Murph
 
Looks nice. Where did you get the little black connectors to plug into the power supply headers?

Edward

I have negotiated a special deal with a local Molex Distributor. You can get them from a number of different sources like Mouser, Jameco, Diigi-Key, etc.

Here is the Mouser info:

Pins 53-8-16-02-0102 $0.06 ea $0.05 ea(100) [32 pins needed]
6 position 538-50-57-9006 $0.79
7 position 538-50-57-9007 $0.85
9 position 538-50-57-9009 $0.90
10 position 538-50-57-9010 $0.76

.156 connectors and pins
Pins 538-08-50-0189 $0.08 ea $0.06 ea(100) [32 pins needed]
6 position 538-09-50-3061 $0.42
7 position 538-09-50-3071 $0.39
9 position 538-09-50-3091 $0.64
10 position 538-09-50-3101 $0.72

Cost of connectors and pins without shipping $9.63.

Don't forget to get your wire too. You will need 22AWG, as anything larger will NOT fit the pins for the little black connectors.

If there is enough interest, we would make these for roughly $20-$25 shipped. Don't know for sure without running the numbers, and I have not run the numbers yet.
 
Selling these wasn't my intention, maybe someday. I just needed a solution so I didn't kill another power supply. I'm all for people making their own, just keep in mind that besides the parts you also need the proper crimpers. If these get made they will be After the nintendo harnesses an would only support the pp7b with the pp7a as an option. -dry
 
I have negotiated a special deal with a local Molex Distributor. You can get them from a number of different sources like Mouser, Jameco, Diigi-Key, etc.

Here is the Mouser info:

Pins 53-8-16-02-0102 $0.06 ea $0.05 ea(100) [32 pins needed]
6 position 538-50-57-9006 $0.79
7 position 538-50-57-9007 $0.85
9 position 538-50-57-9009 $0.90
10 position 538-50-57-9010 $0.76

.156 connectors and pins
Pins 538-08-50-0189 $0.08 ea $0.06 ea(100) [32 pins needed]
6 position 538-09-50-3061 $0.42
7 position 538-09-50-3071 $0.39
9 position 538-09-50-3091 $0.64
10 position 538-09-50-3101 $0.72

Cost of connectors and pins without shipping $9.63.

Don't forget to get your wire too. You will need 22AWG, as anything larger will NOT fit the pins for the little black connectors.

If there is enough interest, we would make these for roughly $20-$25 shipped. Don't know for sure without running the numbers, and I have not run the numbers yet.

Hey Dokert, Big thanks for the part numbers!

Edward
 
Just want to note for anyone wishing to build their own, the Waldom HT-1921 crimpers will NOT work for the Nintendo size pins.
 
The one I built for myself is totally overkill since alot of the pins are paralleled in the power supply so future testing harnesses would have less wire. - Barry
 
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