Out of order mixer, what part could be faulty?

[Bricolo]

Hi all,

It's an old Roland mixer table, not functionning. Plugging the ac socket, and pushing "on" doesn't do anything.

Are there some known problems on such stuff? Something I should look at at first? (the fuse is ok)


Thanks for helping

 

[OliverD]

Sound like a PSU issue. We will help you sort this out.

Some basic questions to get us started:

1. Do you have a digital camera?

2. Do you have schematics?

3. What's your level of experience with repairing electronics?

 

[Bricolo]

Yes, sounds like a PSU problem

Have a camera, no schematics
And I've no experience in repairing "complicated" stuff like that.
I have some "basic" audio diy skills, and I'm learning electronics at school.

Looks achievable 😉

 

[OliverD]

Can you post a picture of the open mixer so we know what we're looking at? (Especially the PSU section)

I guess there are lots of opamps in there, so I'd first check the opamp rails with a DMM. Expect something like +/- 15V.


Caution when you work on the powered mixer, make sure you don't accidentally touch anything carrying mains voltage. Use tape.

 

[Bricolo]

since it's a mixer at work, I'm not sure I'm allowed to post pictures 🙁

I'll have a look at the PS section first, thanks for the hint