I have tried mount ham sticks on SUV and a convertible use trunk lid mount, especially on 40m on the convertible I notice the SWR changes from opening the door and close the door. Now I am quite interested to find out how much radials a car would present to the antenna. Are there any ways to measure or give a somewhat quantified indication of how much radials an HF vertical is lacking? Something that indicates the "unblancy"? Maybe on a network analyzer?
1 Answer
An "analyzer" would indicate the impedance at the feedpoint. You could model the antenna and some radials in 4NEC2 or another program to learn what radials produce the equivalent feedpoint impedance.