I recently picked up a couple of broken Duos to work on in my spare time.
One of them has several missing chips = just leaving it alone for now.
The other is complete, appears to have had chips remove/replaced/reflowed - not really sure, they just look like they have some extra solder on the legs.
I have gone through and removed any obvious solder bridges on the chips before ever plugging it in.
When it was plugged in, there was no audio/video activity and no response from the CD drive when "Run" was pressed. It was on for about a minute and I noticed that the left hand (when looking at the front) 7805 was super hot. Probing around with the multimeter, I found that after that 7805, ground and output (5v) are shorted.
I found a couple of caps that appeared to be shorted, but they were just spots where ground was on one side and 5v on the other - the caps were fine.
I have since removed all of the caps and still have the short.
Anyone know of any components on the Duo that may be prone to shorting like this? I am having a hard time finding the culprit.
The power to the CD side doesn't appear to be shorted. I do have the other Duo to test continuity etc - so I have been slowly muddling through the two boards looking for oddities, but any advice would be appreciated.