Thank you all for the info and suggestions. Actually, the amp was bought from British company Hi Fi and Audio which carried out tweaks for the amp to be used in the UK. They were made in China but adapted for the UK market. Regrettably, they don’t seem to be trading anymore. i believe they were based in Nottingham. Naturally, if they were still around, I’d contact them but this no longer seems possible.
I lost one of me Svetlana KT 88 in my amps ( lost vacuum )and replaced with a full set of JJ what a step down.
Bill
Bill
wirewiggier,
If possible, you need to determine why the Svetlana KT88 lost vacuum.
It would be nice if you could post a complete schematic of your amplifier.
My Datsun 610 destroyed a premium set of radial tires.
I sought out the cause, and had it corrected.
After that, steering, cornering, stopping, and tire life all had a very large improvement.
Just Saying
If possible, you need to determine why the Svetlana KT88 lost vacuum.
It would be nice if you could post a complete schematic of your amplifier.
My Datsun 610 destroyed a premium set of radial tires.
I sought out the cause, and had it corrected.
After that, steering, cornering, stopping, and tire life all had a very large improvement.
Just Saying
Just by way of update, i reset the bias and since then, there has been no occurence of red-plating. I keep my eye on the amp ready to turn it off swiftly at the first sign of anything amiss. Fingers crossed, all seems to be well. I do have sets of TAD, JJ and Brimar KT88s as replacements.
Judging from the photos, it would be very easy to add 330-680K resistors from wiper to the end of each pot. This would solve the problem
Once I worked with a Belgian guy that had such a car locked in a house/building he inherited. There was a new wall made that made getting the car out of the building rather difficult. A really stupid way of dealing with matters or complete lack of communication. Pity as the car was like new. Gordian knot 🙂