> Fixed tuned inputs with a Q of 5 or better are hard to
> come up with if one wishes to cover an entire band.
80 and 160 are the worse bands in terms of BW.
Using a network Q of 5 and 18 ohms load R, 50 ohms source R...
I get 5380 pF/1.84uH/ 8157 pF for 160-meters and an SWR of
1.5:1 at band edges.
That's about 10% BW at 1.5:1 VSWR using normal component Q's
and a network Q of 5. (network Q is higher than the simple Q
Handbooks often use).
So you should be able to do 370 kHz on 80, 700 kHz on 40, 1.4
MHz BW on 20.
Most likely you actually don't need that much Q anyway, you just
have to be sure the second and higher harmonics see a low
impedance and the network matches the load and source. Eimac's
data are just general suggestions and results vary with the actual
operating conditions and circuit.
73, Tom W8JI
W8JI@contesting.com
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