KEL 84 rebuild.

[bob orbell]

KEL is now all done,and looks very good, here is a picture of the inside.

[bob orbell]

The KEL now has a new PCB, waiting for four new capacitors and six new valve bases, the one I removed from the old board dose not go through the holes in the new board, also, fast recovery diodes for HT and Schottky diodes for the ECF80 heaters.

[bob orbell]

Just been looking at the new board, can I drill the holes out to the size of the valve base pins?, there are no top to bottom interlink connections, any one else had this kind of problem. BOB

[bearded fiddler]

I had exactly the same problem when I bought the (then) new PCB model several years ago. My solution was to file down the valve base legs until they fitted, which was a hell of a job. I wish I had had a power tool like a Dremel to do this, but no, it was all done by hand.

[bob orbell]

Thanks Jan, that is a way round it, I don't fancy drilling the PCB, also, I will bring this to Matthew's attention. BOB

[bob orbell]

Just been speaking to Matthew this morning and he is sending me six new valve base's that do fit in the holes, so no need to enlarge the PCB or get the file out, and I have also found three Evox Riffa power capacitors and fitted them. So it should be back together in a few day's. BOB

[bearded fiddler]

Nice to hear this can be solved without hassle. The filing job wasn't something to look forward to.

Jan

[bob orbell]

Fitted the valve base's today and installed the board, checked all voltages and all a little high due to my mains of 249 when testing, the ECF80 DC voltages were 7.55, the Schottky diodes were the problem, so out came the board and I replaced the Schottkys with the bridge package, voltage's now back to good. Sounds very good now, better than before, it is most likely the ER low ESR capacitors. BOB

[bikerhifinut]

Bob I had the same with a KEL84 I bought assembled with the shottkies, i made pi filter that dropped the volts nicely, i think it was about 1R I used, but a bit of ohms law should get you there.

Andy

[bob orbell]

Hi Andy and all, I did think of that when I had the new board out, but the lowest resistor I have is 10 ohms, no good, but I had the bridge package from the old board, so in it went, sound wise, I can tell little or no difference between the two, but fast recovery HT diodes and Evox Riffa power capacitors has improved the sound, plus, all the electrolytic capacitors have been replaced. Nearly a new amp. now. BOB