Multi-tuning AM selector
If you follow the cap switching topology, a PIN diode suitable for use at your frequency of interest (i.e. MAcom MA4PH301) would be less complex than the transistor switch you mentioned in your question.  In the sketch, L1 &amp; C1 form the resonant tank circuit.  R1 is chosen to limit the forward bias current from your control voltage to a value within the limit of your chosen PIN diode.  The PIN diode is acting as a switch, not a variable capacitance device (varactor).







simulate this circuit &ndash; Schematic created using CircuitLab