Duplicating broad band tuned input

[Lane Zeitler]

I would like to copy the design ETO/Alpha used in the mid 70s to mid 80s on their tuned input circuits. They used a toroid in combination with a small cap and resistor I believe. I have the schematic somewhere here in the shack but my main concern is how is the toroid wound?

I have a Sigma XR3000D amp that does not have tuned input on 160, 80, or 40 meters but does have tuned input for 20-10. I have never seen a design like this. Anyway, if anyone knows how Alpha wound the coils I would appreciate it if they could spread the good news. 

Lane
Ku7i
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