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Keeping Linn LK boxes alive for another 20 years

So far this is where I’m at, I have not installed the bridge rectifiers yet. I’m not sure if I can squeeze another transformer in there for the 10v supply or if I will have to go external. Any ideas welcome
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All working well this morning just not sure what the 10 volt supply does ? And how important it is.

I’m not sure if I should go for a smps or another transformer outside the casework.
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The 10v drives the digital 5v supply. Looking at the schematic it seems this is also driven from the +24 raw. Not sure why this is 'or'ed' together. Might be to do with getting the +5v digital supply up first regardless, but it seems a lot of effort. Anyway that would explain why it works without the distinct 10v.
 
I have been using it all night and it sounds fantastic, I have ordered up a 9v toroidal transformer to try and squeeze into the unit but after testing all functions and having a good listen I really don’t see the point in fitting it.
 
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The resistor I had trouble with is R13, visible in the second picture, left board, between D2 and R12. R12 is another important resistor and can be checked from the other side of the board.

Looks a bit better than my Numerik, last year :D
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Got it fixed, thanks to Linnfo & David E.
And still going strong :)
 
I think the cylindrical Brilliants are eminently serviceable. The SPS are a bit more tricky, but, AFAICT, all the parts likely to fail can be found, and the Intersekt series of nearly free LK boxes provides a ready source of replacement 'kits'.

Right now I don't think I'd be looking at a transformer replacement, but it seems dingding has lucked in, which is all that matters.
 
I have been using it all night and it sounds fantastic, I have ordered up a 9v toroidal transformer to try and squeeze into the unit but after testing all functions and having a good listen I really don’t see the point in fitting it.
Check none of the voltage regulators are getting overly hot. U401 takes the raw +24v and produces 6.7v which then feeds U402 to make the +5v digital supply. When the 9v is there it 'takes over' from U401 which effectively turns off. From your pictures U401 has no heatsinking, whereas U402 does. 401 is dropping maybe 15v, so should be dissipating many times the power of 402 and they thought it worth bolting 402 to the chassis.

This is my guesswork from looking at the schematic, I've a Numerik in the loft but I've not opened the box for years. I think it still works, it provided the model for the Brilliant photos above...

The Kairn has a mostly identical 'on board' PSU arrangement, and it makes a substantially greater demand on the +5v line, so probably there's no issue here and you can benefit from Linn reusing layout and casework designs. Worth checking though.
 
Thank you Paul I will check that out, I have ordered up a second transformer so may pop that in just in case. But will run a few tests first.
 
The 9volt transformer turned up today so I couldn’t resist fitting it tonight. I will tidy up once I have done a recap on the unit but for now it’s working perfectly and now running cool. Many thanks to Paul R for his help, I hope this thread will continue as It was hearing a full keltik system in Harrods in the summer holidays back in the 90s that switched me onto hifi so I would love to see them going for another 30 years.
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