mesa boogie m2000 repair

[heliogalvao]

Man, thanks for the yellow cap tip!

I printed the schematics to follow +15 after 7815. Then, reached the tube chan compressor block which has a C95 yellow eletrolytic cap. Lifted one leg and... ...shorted! Turned on the amp and 7815 hot again. So, I checked the FET chan compressor block. Found another yellow cap C90. Shorted! Turned on the amp and got back +15V! =)

Both are yellow, axial, 15uF.

Maybe it is a project problem or a problem regarding production series of these caps...

Next monday I will buy new caps and then send news here.

THANKS AGAIN!!! I CANT BELIEVE IT.

[beatnik]

these caps are quite poor quality. i would suggest since you already have the amp disassembled, change all of them

this amp (like many other boogies ) is not repair friendly at all, it takes a lot of effort to access to the main pcb and put it back together. i think replacing these capacitors might save you some time in the future

[glebert]

I wondered about the low-cost non-contact laser IR thermometers for this kind of work. I've seen them on offer for £15 with a claimed accuracy of +/- 1.5 deg.C.

I've got one of these that I am going to start using for this sort of redneck thermal scanning. The indicator light turns color when you get hot or cold spots. You can scan a lot of components really quickly without contact.

https://www.amazon.com/Black-Decker-.../dp/B0044R87BE

[Sowhat]

I've got one of these that I am going to start using for this sort of redneck thermal scanning. The indicator light turns color when you get hot or cold spots. You can scan a lot of components really quickly without contact.

https://www.amazon.com/Black-Decker-.../dp/B0044R87BE

I've played around with these things and even expensive ones with a video display but I find them to be too fiddley. I discovered that simple is best so I have a spray bottle of pure alcohol and if I want to find a hot spot I spray the suspected area and watch how fast and where the alcohol evaporates. Just make sure your alcohol contains no water... that would be far too exciting if you get my drift.

[heliogalvao]

I couldnt find the 15uF x25V capacitor. Only 10uF or 20uF (both 25V).

I have asked Mesa if I can use 10uF instead of 15uF but they didnt reply. Does anyone here know if I can use the 10uF instead of 15uF cap without side effects to the amp?

These caps are connected to the main IC of compressor blocks (FET/TUBE).

Thanks.

[Leo_Gnardo]

I have asked Mesa if I can use 10uF instead of 15uF but they didnt reply. Does anyone here know if I can use the 10uF instead of 15uF cap without side effects to the amp?

You could use 10 or 22 uF, keep in mind the 15 uF value may be used to set a time constant (attack, decay) in the compressor and substituting a different value will alter that function. OR you could parallel 10 uf with 4.7, another common value, and be near as you can to the original value.

[heliogalvao]

Thank you Leo. In fact, by using 10uF or 10+4.7uF (in parallel) I think it won't change drastically the functionality.

Asking Mesa, they've suggested two 10uF (in parallel). After all, I've decided to use a 10uF+2.2uF x 25V to stay near the original's 15uF x 25V.

Now I have tested and it's working fine! Like new!!! Another good news is there aren't screws and parts left. =)

A special thanks to Beatnik!

See ya.