Total posts : 45366
Thinking SSTran, Ragemaster.. Ground Mounted Scenario..
You can have a zillion feet of ground wires buried under the antenna. As long as they are horizontal, they don’t radiate. If one has the Xmtr mounted 3′ above the common connection point of the zillion wire ground plane with a short radiator in a vertical orentation, the ground wire going from the Xmtr to the zillion wire ground area can add to the field strength. That piece of vertical wire from the Xmtr to the artifical ground becomes part of the radiator. Even though it’s short, it becomes part of a dipole antenna. The longer the vertical ground wire is, the more it becomes a radiating element. That fact is what gets folks in trouble..
An antenna is just a capacitor. You apply a sine wave to it, it tries to find a resonate spot, which is made through inductance, capcitance and resistance. The horizontal part of it just collects alternating energy from the radiating element to feed the coil and other associated circuits the opposite half of the sine wave to help find the sweetest spot towards resonance. Being that we are stuck with a very short “Legal” length radiator, we ain’t gonna find a very good sweet spot, due to the wavelength..
It’s sorta like a ping-pong game. The ground is the champ and the radiator isn’t quite as good. The ground doesn’t miss anything but the radiator misses a few now and then. The radiator serves, the ground returns. The farther away from resonance, the better the radiator is in returning. (They smack ‘um back and forth until the radiator misses one, the radiator serves again) The closer to resonance the system is, the better the ground gits and smacks the balls out into the air past the radiator.. Relatively speaking.. 😉
Now, Back to my Robin Trower Concert..