Replacing SMS cart batteries

[norkusa]

I searched around for threads on this but I only found info on SNES/NES battery replacement. I don't know if replacing the battery on a Sega Master System cart is the same thing, so I figure I should post this anyway.

I just picked up a complete Phantasy Star last week. Tested the saves out and they only lasted about 5 minutes before they were lost, so it looks like I need to replace the battery on it. Opened the cart up and see the battery but it looks like it's soldered in.

So how do I get this out? Which points do I have to solder?

[ApolloBoy]

Try using a hot razor blade to break through the solder. I've never tried this before but it's supposed to work.

[Natty Bumppo]

I would suggest using a heat sink - they are a little alligator like clip that will absorb the heat from your soldering iron so it doesn't go to the circuits and damage them. You can get them at Radio Shack (or an equivalent store).

[InsaneDavid]

Overkill.

Simply desolder where the clips attach to the board and remove the battery and clips as one part. Install a battery retainer (a clip and socket, like what the Saturn uses for its battery) and then you can install / replace the battery as needed. I'm sure you've come across the same when looking up NES / SNES battery replacement.

[Wraith Storm]

... I was going to start a thread and ask the same thing.

I have a copy of Phantasy Star 1 and it still saves perfect! But I want to replace the battery because I don't want to get half way through the game only to have it die on me.

I hadn't thought about installing a battery retainer. Thats good thinking David. Looks like i'm gonna have to visit Radio Shack this weekend.

[alexkidd2000]

Am I the only one amazed that some of these batteries are still holding up 20 YEARS later?