For radios antennas there are two factors. Impedance and length. The legnth is based upon frequency ( a full wave for 75Mhz is approx 74.9" and a 2.4Ghz is approx 2.4"). The length can be shortened to different sizes (75Mhz 1/2 wave is 37.45", 1/4 wave is 18.725" and so on). As you shorten the antenna you lose range. The impedance is the resistance of the antenna on the receiver. Keeping the wire the same length while wrapping around the tube keeps the impedance the same. For 2.4 Ghz radio the hidden antenna should not be an issue. For the older radios as long as the wire length is the same as the original design your replacing, the only thing you will be effecting on your tank receiver is distance and possible interference issues by wrapping a coil and placing inside the vehicle.