A tuned circuit is a reactive load just like an untuned circuit except
its reactance is max at the desired frequency. Any DC resistance such
as the diode and it's load are undesirable as they lower Q.

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73
Hank WD5JFR
"Theo" wrote in message
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"Henry Kolesnik" wrote in message
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Colin
Good on yah mate..
Now to express it another way the winding ratio of the diode
transformer has to be such that when it reflects the diode and its
load to the plate of the last IF, the plate circuit will see the
correct impedance for the IF tube load. Transformers don't have
impedance, only turns ratio to reflect back whatever impedance they
see in accordance with the turns ratio.

Thats fine for untuned transformers, but surely in the case of these
I.F. transformers that consist of mutually coupled parallel tuned
circuits, this must be different?