[Amps] Z of SB-200 input

[Roy]

Hi.
Trying to caculate the input circuit for Sb200
Wonder what  z  does two 572b GG cofigration presents[sb200].
Thanks.
Aron 4x1fq.


Hello Aron,

It is about 125 ohms. If you design a pi-network for that value, using 
variable caps at the input and output, you can tune it easily for unity SWR 
at the input. Example, for 40-meters, C1 = 900pF, C2 = 570pF and L = 1.30uH. 
Operating Q = 2 with these values. Use larger value variable caps so you 
have some range for adjustment purposes.

Good luck and 73,

Roy,   K6XK