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help--help.. i am building a sweep tube amp..4-6kd6 tubes. i can get it to work on 80-40 meters but nothing else.. i need the phyiscal size of both coils for the pi-network.. 10-80 meters or to buy 1 that will work 10-80 meters. better yet 10-160.. i am abt to just put it the junk box.. cant find the phyiscal sizes anywhere..i have read the hand book but cant understand the formlas.. PLEASE HELP.. n4vnl/bob

It's kind of hard to say what's the problem without seeing or knowing what you have.

You could have distributed capacitance and/or distributed inductance in the output network throwing-off your circuit.

Or you could have mutual inductance between the two coils.

Can you borrow a grid-dip meter? That way you can at least check your input network to see if it tunes on all bands.

Jerry

N9LCD