OCF antennas are very convenient as they will allow multiple bands of operation with a simple wire antenna which is fed off center with a 4:1 OCF Current balun with built in feed line choke,
RFI/EMI Solutions from KHz to GHz
Ferrite Slip On Bead, ID = .193in/4.75mm, Mix 43 - excellent tor individual wire common mode choke, 1 piece
FB37-43 - Solid Free Hanging Ferrite Core 80Ohm @ 100MHz., ID 0.193" Dia (4.90mm) OD 0.375" Dia (9.53mm) Length 0.410" (10.41mm)