Vectronics VEC-1290K Manual - page 23

antenna to the low-impedance of the final RF stage transistor.

Jumpers

are used to select the optimum amount of inductance for segments of the AM

band. Trimmer capacitor C11 allows for a precise match at the operating

frequency-or, maximum transfer of RF energy to the antenna.

The pi-

network is in essence is a low-pass filter configuration, and also offers some

degree of harmonic energy rejection.