Rm kl405 issues.

[Syborg]

Hi folks.
I have a set of rm kl405s that are acting strangely.
As soon as they are connected to power they are drawing 10 amps straight away without even being switched on.
I’ve tested them all connected up as standard and I’m not getting any output as you would expect if the transmit relay was stuff shut.
Has anyone else experienced this at all?
Many thanks
Syborg

[ch25]

Broken final(s)

[Syborg]

Oh dear. These are expensive I take it?

[163TM847]

It depends what transistors they are using, MRF455/SD1446 or Mosfet, If Mosfet then its cheap enough to buy a load, I am not 100% sure what mosfets RM KL use but FQP13N10 are the best choice, Or IRF520, [Try not to use IRF520N] and try to get from a reputable source [IE: Farnell], eBay is full of fakes, If it uses MRF455/SD1446 then they are in most cases not worth fixing, The silver or blue amps i found are usually mosfet.

[Syborg]

Mmm. From what I can see this amp uses two of the 4 leg white transistors. Can’t rememebr the number without taking the lid off.
Very odd as the amp hasn’t been used that often and always with about 4w input.

[163TM847]

The schematic states RM1051 which i believe are the same as MRF455 or SDI446's, If just one of the transistors is blown which is often the case it may be worth repairing, But if both are gone i would say they are uneconomical to repair.