I have an old tube radio where the ant. connection had a capacitor connected to it, by replacing it I got better reception. Basically a wire came from ground (chassis) to the capacitor then to the wire wound ant. Unlike my mentioned radio, many tube radios will have a connection for ground and ant. Try adding or removing the ground wire, it depends which way will work better. Sometimes there may be an adjustable screw outside the unit for easy access, check for that and adjust it while listening to a fairly weak station. Otherwise old radios just will not get the reception of a new radio. If all else fails, like Wayne said, get a better ant.