Need Help Modding a AC/DC Power Adapter

[TSX420J]

I have a non working game gear power adapter. I want to swap the components to make it compatible for my CDX. I think this can be done using the existing PCB and Transformer. I need some insight on what to do. I kind of understand how everything works but need a few suggestions and pointers from someone who knows these things.

I saw a CDX power supply on ebay for $79.00, the guy selling it is smoking crack. I need one but not that bad. I also saw some relevant adapters I can buy, but that's no fun.

I know the general components I need, but I do not know the ratings I need to achieve the correct voltage and amperes. I am trying to make it 9.5v @ 1.5a.

Here are pictures of the inside of the game gear power adapter.

[Haunted360]

Maybe these will help you:

http://www.youtube.com/watch?v=qPt0X5s-1JU" onclick="window.open(this.href);return false;
http://youtu.be/cyhzpFqXwdA" onclick="window.open(this.href);return false;

[TSX420J]

Maybe these will help you:

http://www.youtube.com/watch?v=qPt0X5s-1JU" onclick="window.open(this.href);return false;
http://youtu.be/cyhzpFqXwdA" onclick="window.open(this.href);return false;

Yup, I have seen the one about diodes before. Never seen the other one. After watching both I have a better understanding than before. Thanks!

In the pictures of my power supply, there is no linear voltage regulator or trim pot. Does that means that the voltage is regulated by the diodes? I know that it is a unregulated power supply, but how did the manufacturer drop the voltage to 9.5v 1.5a. I understand the transformer drops the voltage, but after adding resistors, caps and a bridge rectifier, is it going to be the same voltage or amps as what comes out of the transformer? I know that the electricity comes out of the transformer in AC. Once it goes through the diodes/bridge rectifier, the electricity comes out in DC. Does the transformation effect the potency of the electricity in voltage or amps? That is what I do not get. Also, can I safely use specific diodes or resistors to get the appropriate voltage amps I need?

In the second video, the guy puts on a pot at the end to dial in the voltage. I thought that was pretty cool but I would not like to add new components to the original design. I would prefer to swap the diodes, resistors, cap and keep the PCB and transformer.

I am looking at buying a BK Precision 2712 DMM for doing all of my testing, current and future projects.

Thanks for the videos. They are very informative. I am very excited about getting the new DMM to be able to run test.

Sorry, I'm a bit of a noob, but I'm at least willing to learn. If you know of any good forums books or anything on the subject, I'd gladly appreciate any leads. Thanks!

[Haunted360]

I dont really do a lot of work with high voltage, but from what I can understand is that the transformers windings is set to output 9.5 volts AC. You can see the separation on the primary and secondary on the transformer. The primary uses the thicker insulated wire, where as the secondary uses the thinner wire. The more wire I think, the bigger the voltage drop.

The diodes on your power supply (SEGA) look like a full bridge rectifier. The voltage is converted into DC and the capacitor smooths things out (3300uf which is a lot).

Why not just get a universal power supply already set at that voltage and amperage?
I am sure they would have one at radio shack

Should not really modify an existing power supply if you dont know what you're doing. Things wont end well...

[TSX420J]

I don't really do a lot of work with high voltage, but from what I can understand is that the transformers windings is set to output 9.5 volts AC. You can see the separation on the primary and secondary on the transformer. The primary uses the thicker insulated wire, where as the secondary uses the thinner wire. The more wire I think, the bigger the voltage drop.

The diodes on your power supply (SEGA) look like a full bridge rectifier. The voltage is converted into DC and the capacitor smooths things out (3300uf which is a lot).

Why not just get a universal power supply already set at that voltage and amperage?
I am sure they would have one at radio shack

Should not really modify an existing power supply if you dont know what you're doing. Things wont end well...

Understood. Im still going to try. lol. Ill be doing all of my testing outside lol. Im a novice with electronics but would like to learn a lot more. Thanks for the tip. Dont worry though I wont be doing much testing on the CDX till I know for sure that any of my experiments are safe. Thanks!

[Haunted360]

Okay. Just dont touch anything while it is plugged in. Remember that, and you will be fine.