Chip board repair

[@rt]

Hi Guys
I’m looking for suggestions on what the next course of action for attempting repair on this board should be.

It measures 12 Ohms across it’s power supply, measured across any of it's six electrolytic capacitors.
Of course the caps themselves are the first suspects so I have replaced all six,
and that’s all I’ve done so far. The measurement is still the same.

On powerup, most of it’s chips heat up quite hot to touch. which might suggest they are not getting a supply,
but why the measurement close to a short across the supply?
I’m reluctant to power it without having found something else wrong, as the programmable chips are
irreplaceable and any left working can be used as spares for another unit (which I do have a working one).



paid $500 on eBay for this thing :rolleyes:
Cheers, Art.

[Srbel]

Get one chip out of the socket, then measure the resistance of the supply rail again. If it still shows low ohms, remove next chip, until you find which one is shorted.

[@rt]

Yeah I’ve already begun that... since the board looks clean,
and after electrolytics, there’s really only decoupling caps and chips left
If it’s a chip that isn’t socketed I suppose that’s a good thing since it will be replaceable.

[@rt]

It was the Altera, so bad news for the unit, but thanks for the reply.