With a CB antenna, you are unlikely to notice any additional "static" in your receiver. The post about "corona" is actually most accurate. And it applies mostly to Amateur and commercial, high powered HF operations. It is when atmospherics, temperature, humidity and electron particles are at juuuuuust the right combination to cause "lightning" to emanate from one's antenna. That is the "corona" and can be quite a light show! Accompanied by a "BZZZZZZZZZZZZZZZZZT" you can see AND hear, there will be little bolts of visible electricity coming off the tip of the antenna. Particularly "exciting" (pardon the pun) at night. Now. What that little ball does is to provide a smoothe, round surface at the tip that makes it difficult for those little static charges to take hold and "jump" to the surrounding air. While they can occur at any frequency and any power, it mostly happens at lower frequencies and high power levels above 250 watts. One hundred sixty meters
(1.8 MHZ) is quite susceptible to this and I've seen operators take a wad of chewing gum and roll it into a smoothe ball, then put it up there to stop corona (temporary solution)---anything to stop this from happening. With that said, corona is NOT a good thing. While it might be fun to watch (stay OUT of the way of it), it makes the SWR shoot to the moon :shock: and certainly is not good for the equipment. So if you are doing it to show somebody how "powerful" and big your station is, you might regret it if you keep creating corona, and you wouldn't want to "shock" or burn a bystander. Luckily, while
most corona will appear at the tip of the antenna, it
can occur right AT the loading coil or anywhere along the radiating element, so keep onlookers away. Fortunately, corona, as I said, usually shows up at the tip of the antenna above the reach of spectators, and it is because the highest RF current is up at the tip.
A buddy of mine bought a 12" X 18" , 160 Meter bugcatcher some years back when Henry Allen was in full swing with the Texas Bugcatchers. Installed and tuned for
1885 KHZ, Jim quickly found that, using an SGC Smartcube (500 watts), corona would develop in a heartbeat. He machined a HIGH 1" corona ball for the whip and it would STILL go into corona at times!
In broad daylight, the whip would shoot fire a foot wide in little "lightning bolts" all around the tip!
BUMMER! "Cute" to look at, impressive to non-techs, but not good for the equipment! When it started doing that, the amp would simply kick out due to the extreme SWR generated making it impossible to talk. So he abandoned 160 meters. Haven't seen much corona since from 75 UP even with 500+ watts!~
Hope this helps explain the purpose behind the little ball on your whip!
73
CWM
