Jaguar Power issue

[sparf]

I have a new problem. This time it's an Atari Jaguar console. It simply doesn't power on. The power supply is good because it powers my other Jaguar up just fine.

Things I have done:

-Checked for bent pins in the cartridge slot.

-Cleaned the cartridge slot

-Tried a few different games, having cleaned each one and tested it on another Jaguar Unit.

-checked the board for obviously blown, bulging, or damaged components or solder points

-checked the nearest capacitor to the power connector, and a few others. Get potential voltage across many but not all.

-Checked the switch. Get voltage across its solder points/poles.


At this point I don't know exactly what could be fried. For reference, the system worked, then was put away, and when it was pulled back out during the brief time I owned a Jaguar CD, it simply ceased to power on. Also, its power adapter is different than the one with my other Jaguar. The one that came with it is marked for Jaguar (molded logo into the power brick like a Sega adapter, rather than the silver label that my working one has) does not power on my good system.

I'd love to see if I can get this working. No huge deal if I can't but Anybody have any ideas for me to try?

[MASTERWEEDO]

I also have a Jaguar that wont power on.

[raylydiard]

Try finding a 7805 regulator replaceing that fried part and will work again.

[sparf]

A 7805 regulator?

Sorry, but is that the part on the board, or the part I need to look for as a replacement piece, or both?

I found a chip that another site has shown and listed as a voltage regulator at U38. There is a tiny, tiny bit of discoloration as if perhaps it tried to melt but didn't melt all the way through. I'm attaching a picture of the whole board and the chip in question.

If that were to be the failed component, how should I go about testing it to make sure?

[bust3dstr8]

Look up the data sheet for that chip and test the inputs and outputs with a meter. I can't tell from this picture for sure, but if the chip has a discolored circle in the center there is a very good chance it's cooked.

[FABombjoy]

I've seen pics of U38 with a hole in the center, just about where that discoloration is visible. They are what typically fails in a no-power-on situation, especially after ruling out everything else as you have.

Shameless plug: I sell them here. Pinout and datasheet is here.