5Y3 or fuse blow on LSS : solution after a discovery

[srvmac]

Hello Boogie Men ,

I'm Sebastien from FRANCE.

After reading all the posts on the 5Y3 and Fuse blow up on LSS, I discover someting strange that I want to explain here.

Maybe it could help some owers. Maybe not but its works for me.

I've ever tried 2 5Y3 NOS tube to replace the Sovteck or Mesa Stock Tube without good results : fuse or tube blow sometimes and the problem persists.

The LSS seems to be very sensitive to electric stability. So the first thing is to use a surge protection when you plug it. Moreover, always use a T fuse (temporary fuse).

The second thing I noticed appear when you switch off the amp :

Take care of the wattage switch : Put it on 30 watts position for the 2 channels. Don't let it on 5/15. So the solid state rectifer is used instead of 5y3 when the amp is stopping.

Same action when you start it again : put all the wattage switches on 30wts.

When the amp is ready to play, stand by ON and switch AFTER on 5/15wts.

The amp works well on all positions now.

Don't forget to replace it on 30 wts before switch off.

The problem is solve for me with this method.

Anyway, it seems to have a conception mistake on the circuit board or transformers.

Waiting for your replies and tests.

Thanks a lot.

Sébastien - France

 

[ricardo loma vista]

Sebastien,

What do you mean by a "temporary fuse" or "T-fuse?" Do you mean a Class T current limiting fuse outboard to the amp?

thanks Ric

 

[jjboogie]

What do you mean by starting again......do you mean turning it on and off?

I also had my amp not plugged into a surge protector and I had been playing a few times and the power in my house go out and the amp suddenly be cut off! I have had surges as well....I was stupid by not having it plugged into a surge protector.

 

[srvmac]

Hello

I mean a TEMPORIZED FUSE. It blow slowly and not quickly.

The matter is the LSS is sensitive to the power changes. And there is an effect on tubes, particulary on 5Y3 when using the 5/15wts position.

What do you mean by starting again......do you mean turning it on and off?

Yes, you have just to put it in 30 wts position each time you turn it on / off.

Once the amp is working, you can change the wattage mode without influences.

It works well for me using this method. I've changed all the amp tubes also.

A mod exists to solve the problem completely but I have to bring back my amp to mesa repair service.

Thanks !

Sebastien

 

[srvmac]

mmm sorry guys,

After a lot of tests, the problem continue.

I have to bring back to my dealer for repairing.

Sorry again...

Sebastien