Like an english sports car, more or less.
Sweet, high-performance when everything is right. Trouble is, most mechanics don't understand it and will usually make things worse if they play "pin-the-tail-on-the-donkey" with the thing. If you can find a mechanic to keep it on the road, it's a joy to drive. And when it breaks, you'll be better off to take it to someone who understands the thing.
Trouble is, that's the fella who made them. Ray Felts, somewhere in North Carolina. His phone number's gotta be in a dozen posts on the board's archives.
The internal design has evolved over the years, so even if you had ONE diagram, there's little chance it would be valid for your unit. Different tube types have been used in them, changing every couple of years. Gotta figure he'll buy a couple of years' worth of tubes, build boxes with those, and then buy a large load of whatever tube is cheap the next time around, again and again, like Bill Murray in Ground Hog Day.
"Elkin amplifier" is like "Ford Truck". What's under the hood depends on what year it was made.
Best advice is to remember, when it breaks, you have the pieces.
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