VOGONS

Search

Common searches

MT-32 front panel button replacements

Topic actions

First post, by TheMobRules

Posted on 
User metadata
Rank Oldbie
Rank
Oldbie

I have an MT-32 which works fine but a couple of the front panel buttons aren't working. I opened it and disassembled the non-working buttons to see if I could fix them. Roland used some Alps membrane-based switches ('SKELAF') and in my case the elastic rubber membrane completely broke on these 2 switches, so there's no simple way they can be fixed. Also, this type of switch is not available to purchase anymore so I'm looking for alternatives.

From what I could find on DigiKey and Mouser it seems 6mmx6mmx9.5mm tactile switches with 2 terminals should work, at least when it comes to footprint and size. Not sure if there's anything special about the original switches that I should consider, though I have noticed that pressing the original buttons (the ones that still work) the pins are not shorted, instead I get between 1 to 5 kohms. Is that because they are worn or am I missing something?

I'd like to hear opinions, especially if someone already had to replace the switches on their own unit.

Reply 1 of 2, by esher

Posted on 
User metadata
Rank Newbie
Rank
Newbie

According to MT-32 service manual schematic, there is 1S2473 diodes before every switch, may be you measured with them?
In the schematics it is just a switch, desolder the working one and check it separately. If it measures (desoldered) some kOhms - it's not normal.

Edit: there is video on youtube https://www.youtube.com/watch?v=BzbRcQHq1M8
where the author measures the same resistance. May be it's normal for this type of switch.

Reply 2 of 2, by TheMobRules

Posted on 
User metadata
Rank Oldbie
Rank
Oldbie
esher wrote on 2024-10-27, 19:05:
According to MT-32 service manual schematic, there is 1S2473 diodes before every switch, may be you measured with them? In the […]
Show full quote

According to MT-32 service manual schematic, there is 1S2473 diodes before every switch, may be you measured with them?
In the schematics it is just a switch, desolder the working one and check it separately. If it measures (desoldered) some kOhms - it's not normal.

Edit: there is video on youtube https://www.youtube.com/watch?v=BzbRcQHq1M8
where the author measures the same resistance. May be it's normal for this type of switch.

Yeah, I stumbled upon that video before seeing your post... it's strange. I think I will try soldering a regular tactile switch and if it works fine I'll order some with the proper dimensions.

Go to top of page Go to top of page
Back to Sound
Close window
Close window