Any Jim Kelley Owners Here?

Calel

Hey guys,

In brief, got a JK combo from the US, got damaged by UPS, currently fixing it. The amp is running on 120v and we want to rewire it for 240v. I reached out to JK and he told me it was totally doable but did not give me any details at this stage. Asked Suhr as well and for some reasons they are pushing back, even though the amp has been discontinued so it is not like there are a lot of options out there.

There is a multi tap in the primary winding of the power unit, there are three unused cables, yellow, red, and green (sounds like Lethal Weapon plot when they have to defused a bomb).

Does anybody have done this for a US JK? If so how?
Alternatively if you do own an European version, could you let me know which cables are wired and how, so that we can replicate here?

Any input is much appreciated, would rather avoid having to run the amp through an external voltage scaler thingy.

jpfamps

Any competent tech should be able to work out if the tranformer can be wired for 240 V mains.

Else it shouldn't be too hard to find an off-the-shelf replacement I would have thought.

DJH83004

There are a couple of possibilities depending upon the primary winding, it may be a straightforward multi tap design e.g 0, 120, 230, 240 etc. Or it may have two separate 120v windings which will need wiring in series for 240v operation. Either way it can be worked out but far simpler if they would just send over the connection details, it's hardly intellectual property is it

Ossyrocks

I worked on a couple of Jim Kelley amps years ago. The transformers looked custom to me and were huge!

They put 500v on the anodes of those poor 6V6's ! Only NOS JAN stuff could take the heat.

Be very careful!

Rob.

Dominic

why not just buy a good outboard transformer

Calel

DJH83004 said:

There are a couple of possibilities depending upon the primary winding, it may be a straightforward multi tap design e.g 0, 120, 230, 240 etc. Or it may have two separate 120v windings which will need wiring in series for 240v operation. Either way it can be worked out but far simpler if they would just send over the connection details, it's hardly intellectual property is it

Thought about it too but I am clearly not competent in the field. Totally agree with you re IP, very surprised they push back on such a minor item that would allow me to run a discontinued amp in a sustainable manner.

Calel

Ossyrocks said:

I worked on a couple of Jim Kelley amps years ago. The transformers looked custom to me and were huge!

They put 500v on the anodes of those poor 6V6's ! Only NOS JAN stuff could take the heat.

Be very careful!

Rob.

Noted.
Thank you.

Calel

jpfamps said:

Any competent tech should be able to work out if the tranformer can be wired for 240 V mains.

Else it shouldn't be too hard to find an off-the-shelf replacement I would have thought.

Ah...I am sure we will figure out as you said, but if we can't, you're up next!