Here’s the simplest antenna that you can build to transmit with your HT or mobile rig when you have nothing else to rely to. The configuration gives you a 3.5dBi gain and it is simple to construct when you’re at outdoor.
I built this antenna, specially for hitting repeaters during lightning storm, as my usual high mounted antenna might attract lightning.
This antenna can be built using any conductive wire. Though, for my configuration, I use thick copper wires with the length A = 0.525m and B=0.4815m. The A-B angle is about 100-110 degree. It gives SWR 1.0 between 145.5MHz – 145.8MHz and SWR 1.3 at 148.0MHz, the edge of 2 meter amateur radio band.