A501 soldering a new coin cell

A501 RAM expansion with 512 Kb for the Amiga 500

After the leak work on the A501 memory expansion, i had to replace the battery for a new coin cell.

See also:
Commodore Amiga 500: Amiga 500
A501 memory card expansion for the Amiga 500: A501 expansion card
Working out the A501 leak: A501 card - leak work
A501 bug...real bug!!: A501 real bug

I used: coin cell socket, coin cell,Soldering Iron, Multimeter, wire, and 1 diode.

This is the Schematic i got in internet, aminet i think...

Very easy, identify the + and - on the A501, then put the coin cell after the - and the diode between the + of the coin cell and + of the A501. The Diode must have the end stripe turn to + side of the A501. the diode is to prevent that the Board of the Amiga charge the cell, it’s not a battery like the previous one, so it cannot be charged or it could explode. The diode only allow one direction, so it will not charge the cell.

As the front side of the A501 had the leak treatment i choose the other side to start working. As you can see here, it has no wires yet.

First 2 wires soldered in the card. Left wire the - right wire the +

I had to get a place to fix the coin cell, i didn’t want to drill the card, so i put it in one corner were it don’t interfere with nothing. I solder the coin cell (-) with the (-) wire as you can see in top solder, i used the card hole to fix the coin cell. Then the (+) in bottom solder, the wire is on the other side of the card and it gets to this side by the top hole in this picture.

The solder of coin cell (+), this wire was difficult, a lot of solder, and it is not as i wanted, must try to get this part better.

Here is the other side of the card, you can see the coin cell (+) and the diode that is bend in both sides