VHF signals from a mobile station using a vertical whip antenna will normally be best received using a:

For the best reception in radio communications, the receiving antenna should have the same polarization as the transmitting antenna. A vertical whip antenna used by a mobile station emits a vertically polarized signal. To match this vertical polarization and avoid severe signal loss, the receiving station must also use a vertically oriented antenna. A vertical ground-plane antenna perfectly matches this requirement. Using a horizontal antenna, such as a horizontal dipole or a horizontal ground-plane, would result in cross-polarization, which drastically reduces the received signal strength. A random length of wire has unpredictable polarization and will not perform reliably.