In response to Rich's guess reduced Q would hurt matching
range.......for a the ETO Q of 5.3 into 50 ohms..... and pi- tank
inductor fixed at 21.57 uH and L inductor fixed at 7.255 uH.....
760 ohm load, Cp 600 pF, Cload 695 pF
325 ohm load, Cp 499 pF, Cload 895 pF
50 ohm load, Cp 444 pF, Cload 1646 pF
22.8 ohm load, Cp 499 pF, Cload 895 pF
8.5 ohm load, Cp 619 pF, Cload 1620 pF
The matching range is obviously limited by the capacitor range, not
by Q. Increasing Q by padding the capacitors will often reduce
range...instead of increasing it.
Pi-L's are pretty neat networks, since they function over a very wide
QL and impedance range.
I have to wonder.... what is wrong with using a Q of about 6??
73 Tom
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