[Delta77]

I recently sent my (CSP3) Preamp in for troubleshooting the noise coming through the headphones.
They said Steve replaced the fuse for the Rectifier..

This is leading up to me knowing how to prevent this from happening again, or for it to happen on any other equipment I have..

Can anyone lead me to any Info on how to tell if the tube are good or not, or explain from their own perspective..??

I believe it might be (1) of the (3) Sophia Electric 274b's.. How do I tell if it's good.. I believe it also blew the fuse in my Modwright power supply as well..

Thank you,
 Delta..

[SteveFord]

If you have a lot of tube gear a tube tester is a good thing to have.
Who knows what evil lurks in the hearts of tubes?
My tester does (at least at that moment in time).

[Tyson]

If you have a lot of tube gear a tube tester is a good thing to have.
Who knows what evil lurks in the hearts of tubes?
My tester does (at least at that moment in time).

"The Shadow knows!"

[FullRangeMan]

You should see this prob in detail with Decware,  basically they said the fuse was making noise 

[rudolffzigray@gmail.com]

I have used many Sophia 274b rectifiers.  Mesh and solid plate.  They do fail and blow fuses.  Draw back of a wonderful sounding and frankly cool looking tube.  Keep some less expensive rectifiers around that are direct placements.  Also keep an inventory of fuses.   Replace the fuse, it’s doing its job. Fire it up with the same rectifier if the fuse blows again replace it and use a different rectifier if it stabilizes and doesn’t blow a fuse it’s most definitely the Sophia 🤷🏻‍♂️   Of course if you have a tube tester that’s another way.  But I imagine you don’t because of the nature of your post. 5u4g is a cheap enough replacement to keep on the shelf.  Cheers.