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
Available as a Unun for 50 ohm coax to 75 ohm coax or 75 unbalanced load or as a Balun for 50 ohm coax to balanced load such as a low (less than a wavelength high) dipole with either side eye bolts and halyard hoist or as post mountable top studs output.
This is an impedance transformer for 50 to 75 ohms and may require a additional feed line choke to keep common mode current off the coax braid.
CB-1.5-1500EB is useful for a dipole center feedpoint for low dipoles with 75 ohm antenna impedance.
Top stud version also useful for 75 ohm ladder line to coax interface