The humble Roland M-64C memory cartridge which was used to store data on soooo many Roland synths, drum machines and other gear, back in the day. The problem is, that just like the memory inside your favourite eighties synth, the memory in the M-64C is retained using a small battery. These cartridges have stored our patches for decades but the internal battery won't last forever. Here's a little post on the Roland M-64C battery change procedure.
Yes, I know there's quite a lot of clever people out there, who have made some awesome replacements which have huge memory storage and no battery but many of us still have M-64Cs and if all you have to do is change a battery once every couple of decades, then why not?
The case of the M-64C is held together with only two screws but... you'll have to remove the label to open it. YouTube videos suggest that the label is cut but actually, that's not necessary. The original Roland label is printed on to a type of self-adhesive metalized medium and NOT anything that's paper based. Hence, if you're careful, you can peel it off and there's no need to destroy it. The customer who supplied the example pictured in this post, unfortunately didn't know that! 🙁
Once open, make a note of the orientation of the battery. The positive terminal is facing the top of the cartridge, furthest away from the edge-connector.
The battery is a CR-1/3N which is (still) readily) available although it might be challenging to find one with solder tags. Yes, that's right. The CR-1/3N normally turns up WITHOUT solder tags and if you're like me, then the idea of soldering directly to a battery, isn't particularly appealing.
Okay so I need to own up! 🙄 I thought I'd try something. Your average CR-1/3N has a capacity of about 160mAh. The CR2032 however, has a capacity of about 210mAh and so I thought I'd give it go, LOL. There was just NO WAY I could get the CR2032 to fit inside the M-64C case, LOL. There goes that idea!
Performing a Roland M-64C battery change isn't as difficult as you might think and as mentioned, the CR-1/3N battery is still available. The annoyance however, is that you might have to scrap the label. Hey but don't worry. Half-an-hour with a ruler and a little Adobe Illustrator magic and....
I'm currently designing a replacement self-adhesive label for the M-64C which I will make available soon.
If your M-64C label is a bit tatty, then watch this space. 😎
UPDATE - 5th July 2022
I got these back from the printer today!!! 😀