Kahenraz wrote on 2022-09-11, 20:03:

GuillermoXT wrote on 2022-09-10, 04:01:

Do I also have to open my Roland SC 55 ST or does mine not have a battery?

The SC-55 ST does not have any front panel controls, so there is no use for a battery. I've opened these units up and can confirm that there is no battery present.

I was lucky again thanks for the information 🙂👍

I will get a Kawai GMega (version with display) in a few days and I read that the battery was glued on in this devices? I don't find any information on youtube or anywhere about how to change that battery.
Any help is much appreciated!

Jugger69 wrote on 2022-09-26, 17:33:

I will get a Kawai GMega (version with display) in a few days and I read that the battery was glued on in this devices? I don't find any information on youtube or anywhere about how to change that battery.
Any help is much appreciated!

https://www.wavetable.nl/wp-content/uploads/K … nals-scaled.jpg

As you can see the battery is indeed soldered in place but is exchangable for a straight (standing/vertical) battery holder + CR2032 coin battery.

Thanks a lot! Would this holder fit?

Jugger69 wrote on 2022-09-29, 09:24:

Thanks a lot! Would this holder fit?

I cannot be 100% sure since the picture does not show both sides of the battery connections. I don't have the GMega at hand now so I can't check it either. It may fit but it may well be that the original battery solder lugs are one pin on each side.

My guess is though that it would fit. Another option is to take a coin cell holder with short wires. The holder can then be taped somewhere with double sided tape or something.
Something like this: https://nl.aliexpress.com/item/1005003712085342.html

If you're already planning to solder, may as well remove the old one and find out. The replacement parts are also cheap enough that you can just buy them with good intentions and little worry if it's not the right one.

Unless you plan on modifying any of the features, there is no reason to have a battery in one of these. Especially for games.

Thank you both. I will open it up this weekend and have a look for myself. 😀

Pictures or it didn‘t happen! Please 😉

Yeah. I hear you. Will do.

Update: The internal battery is soldered - its a CR2450 battery. There are 3 holes to connect the battery holder. So the shown holders should fit. I ordered some from amazon and I will show some pictures when I remove the old one and install the new one.

I exchanged the soldered-in battery in my Kawai GMege for a CR2320 battery holder.

1. Open the case (5 screws, 2 on each side, 1 on the back - screws are equal in size) . The battery is located in the rear.
2. Free the mainboard. There are 4 screws in the corners and 6 more on the back panel. Warning: there are two screws which are not equal to all the others - the one over the RCA sockets and the one over the serial connector. Lift the mainboard.
3. Desolder the battery - 3 pins - I used a desoldering gun. Fun fact: The "old" battery showed no sign of wear and still had a voltage of 3.1V - not bad at all!
4. Bend the battery holders pins a little so they fit into the holes. Solder in place.
5. Put together again.
6. Damn! The Kawai doesn't like loosing the battery power and its showing some error message after powering on. I did a GM Reset followed by a Factory Reset and all was well again! 😀

• GM Reset: Push “>” + EXIT” simultaneously.

• Factory Reset: Push “SYSTEM” until the display shows “FACTORY RESET EXEC?=N/Y” then answer “YES” twice by dialing wheel to the right.

Nicely done!

It turns out that Roland SC-55K does not have battery inside.
Since that "Karaoke" model haven't been mentioned here I thought I share my findings so you do not have to open yours.

Massive thanks for this thread! I just checked the battery of my new SC-55, looked alright, but replaced it with a new one, just in case.

Are the bigger caps glued to the mainboard?
my SC55 battery has leaked, I will not put another one in and use some alcohol to clean it.
hopefully this will not cause any damage.

canthearu wrote on 2021-09-30, 04:10:

I did open up my Roland RA-50 arranger (arranger with MT-32 synth)

TY for pointing out the RA-50s need checking. Did mine and the battery still looked pristine, but a shiny time bomb is still a bomb.

dr.zeissler wrote on 2023-03-15, 17:04:

Are the bigger caps glued to the mainboard?
my SC55 battery has leaked, I will not put another one in and use some alcohol to clean it.
hopefully this will not cause any damage.

You need to use vinegar to neutralize the acid. Then follow it up with alcohol to remove the vinegar. The alcohol is helpful, but I don't know if it's enough for a single pass.

If the battery acid has gotten through the solder mask and into the PCB, you'll have to remove the surface of the board to prevent it from continuing to eat through it.

If you're already inspecting the board, make sure to check that the adhesive isn't also destroying the PCB. Another time bomb!

Re: PCB destroying adhesive found in my Roland Sound Canvas SC-55mkII

Thx this is how they look like (SC55/MT32/CM32L). As I said I only cleaned the SC55 with alcohol. RA50 and MU50 are noted opened jet.
All midi devices work as they are intended,

A few tips from me regarding some MIDI devices:
*Roland RA-50: does contain a battery that is similar to the MT-32.
*Yamaha QY-8: does contain a barrel form battery that is needs to be desoldered.
*Yamaha MU500: contains no battery, so don't worry about that.

Swapped the battery of a Yamaha MU80. This is how it started:

The board removed from the case:

Interestingly one of the chips has something extra mounted underneath:

I replaced the soldered dead CR2450 with a CR2032 holder. As a CR2032 has only a third of the capacity of the original battery, it will likely only last a few years instead of the 20+ of the original. But I don't care as replacing it is easy, and CR2032 are a bit easier to find.

The cr2032 holder is a cheap one from ebay, its two legs fit well into two of the three holes of the CR2450.

Soooooo guess what I found when I checked the battery in my SC55 that had just started and hadn't made it's way down to the PCB yet...

I'd been meaning to check the battery on my SC55 for a while, but I wasn't in any rush because despite normally being really paranoid about removing batteries, I've yet to find one that actually leaked. Well my run of good luck ended today.

On a whim before bed, I decided to go ahead and check my SC55, and guess what? The battery was leaking, but it hadn't made its way down to the PCB yet. It was all still contained in the battery holder. This was an extremely close call though, it was leaking pretty good.

I'm about to go check every other device I haven't checked yet in my collection. Going to be extremely tired going into work tomorrow, but worth it.