Roland D50 zener diode voltage

[Java]

Hello everyone , i need some help about roland D50 , i need to replace some diode on switch board panel but i can not find the voltage of that so i am not able to order the right one is any body can give me some information about the viltage and type of the diode that i have to order ? Many tnx i have attached some photo if that thank u

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[Grumble]

This is NOT a zener diode, but a fast switching diode 1SS133 I found this by looking at the Service manual where at page 37 you find the diodes used in the Roland D50 listed, and there is just one type of diode on the panel board, being the 1SS133.
I think you can replace it by a 1N4148 diode.

[Java]

Is the same if i use no any diffrent votage ? I search for diode 1Ss133 if has two type small SIG what is that ? All they are same ? Many tnx thank you

[PHOBoS]

They are most likely used as anti ghosting diodes which prevent errors when buttons are connected in a matrix and you press a couple
at the same time. Since it's low current and low voltage most standard diodes should suffice (like the 1N4148 Grumble mentioned).
I am not sure what you meant with your last question.

also

[Java]

Thank you

[PHOBoS]

I am curious, why do you think you have to replace the diode ?
is one of the buttons not working ?

[Java]

Yes one one the bottoms stopped working do i replaced the switch amd still did mot work then i checked the diode i found on leg was broken i replace with other to see is the resone didoe and i t was causing the reason that is why , so for sure i van use the one you menttioned as replace one ? Thank you

[PHOBoS]

ah ok, then it obviously is the diode.
yes, you can use the 1N4148 (or 1N914 or most other diodes)

[Grumble]

I have read that breaking of the legs is a common defect in circuits using the 1SS133.