Help with power computing amiga 500 trapdoor ram expansion

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This ram expansion module came with an old 500 I picked up recently.

I can't identify which model it is based on any of the databases, and the card has no model markings.

It appears to have 1.5mb of ram chips. 12 ea 256k x 4 chips

The first thing I noticed is the connector going from the expansion card to the Gary has a broken wire.

Even with this wire connected the ram isn't recognized by wb 1.3 or my aca500+ card diagnostics screen

The card also appeara to have been modified. There are two cut traces and two very fine jumper wires run on it.

I am hoping the card can be identified and has some kind of common mod done to it that I can troubleshoot.

There were no switches wired to it but there are two jumpers in place. There is a third jumper header with no jumper.

I will add the photos as soon as I figure out how to do that.

Folder link to 5 photos
https://www.dropbox.com/sh/gbja859f61kr6pa/AADYsav94Bp5oxZEjn4P1V9aa?dl=0

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Any ideas?

[rkidd7952]

Hi,

I don't have any firsthand experience with the board, but I have a couple thoughts on things to investigate. Do you have a multimeter handy?

It looks like there might be some corrosion from the (now absent) clock battery. The horizontal traces running near the battery terminal in 'Photo Feb 15.jpeg' look like they might be affected. In 'Photo Feb 15-2.jpeg', there are a pair of 47 ohm resistors on the right side that might be corroded as well. The trace coming off the right leg of the lower resistor looks like it might be broken, right at the 45 degree turn. If you have a multimeter, inspect those traces and see if you have continuity.

For what it's worth, This board looks pretty similar to http://www.bigbookofamigahardware.co...t.aspx?id=1099 as far as the component layout and Gary adapter. Unfortunately, there's not much info on that page.

Robert