Total posts : 45366
Well here’s what I get from EZNEC.
Antenna: 102″ (CB whip)
Antenna diameter: .2″
Elevation to base of antenna: 3 meters.
Source: 3 meters (base of cb whip)
Load: 3 meters (base of cb whip)
Length of ground lead to ground: 3 meters.
Results: minimum SWR with j=3308 (capacitive reactance of antenna equivalent to C=29.9pf.
The type and quality of the ground only changes the R part of the antenna reactance, not the J part. The better the ground, the lower the R part of the reactance. This demonstrates that when you cancel the J part with a loading coil of equivalent and opposite J, you are left with just the R part. The better the ground the lower the R.
EZNEC allows you to play around with the ground quality. This doesn’t change the antenna J part of the reactance. However, the better the ground, the less loss you will have. Also, your transmitter should be optimized to drive less than 50 ohms if you have a very good ground (maybe in the range of 10 to 20 ohms).
Phil B
