Igor says;
>and the many large megawatt now quite Russian SW broadcasters used >similar
techniques to quite down these big tubes
There was a book by W. O. Brown of Marconi, probably long out of print now.
He had a whole chapter on parasitics, and one technique for high power
( 50kW and up!) that often worked was something like a 200 ohm rod resistor,
attached at one end to the plate and just sticking out in the cabinet, with
the other end unconnected. It looked like a lossy open circuit quarter wave
stub because of the size - around 10 inches long. It was a bit critical as
to where it went. Point is that the techniques in tx's at this level are a
bit different to our power levels. K5PRO is the guy to comment on that.
At those power levels, it's all a bit scary!
73
Peter G3RZP
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