Topband: BOG antenna

[Tom W8JI]

> It's refreshing to get input from many sources. I always believed that the 
> static was not from a nearby tower as I have three close by.  The BOG 
> antenna did not hear the noise, but other antennas did.

A nearby tower is just one source, Bruce.

> In broadcasting it is known  dry, high speed blowing snow can cause 
> dangerous voltages on an antenna. The first key word is dry, second key 
> work is speed.

That probably doesn't mean much, because towers and well insulated antennas 
charge just from a modest dry breeze. If someone walks back by the creek and 
touches the insulated tower there, even on a clear day, there is a good 
chance they will get knocked pretty hard.

> Think Guy K2AV has it close but I can not help but think that rain drops, 
> and snow flakes, due to their speed, carry the charge.   But as in the 
> case of lightening the direction can be argued. Guess something on ground 
> has a sharper point than a thunder cloud. Then there are cloud to cloud 
> strikes. Hmmm. The sharpest cloud ?   whoa !

I think the real tests are:

1.) It is very well established that the highest and most pointed antennas 
or structures have the most p-static by far. Usually any lower antennas, 
even those struck  from a  side angle by the same precipitation,  are 
usually dead quiet or very low noise. If the charge was carried by 
particles, it would be the same or similar on all. It isn't. The difference 
in noise of antennas indicates it isn't normally particle charge.

2.) Even without moisture or particles, inclement weather or even dry winds 
bring p-static. No particles, yet the static occurs. This indicates corona 
to the air.

3.) P-static normally vanishes immediately following a strike, and then 
builds rapidly. This indicates the noise is corona to the air.

4.) Many people have bare antennas some small or modest distance above 
earth, and never have p-static issues. If it was precipitation or particle 
borne charges, nearly everyone would have identical results with bare 
conductors. The odd-men out would be those with quiet, bare, antennas of 
almost any type.

5.) The effect is very clearly height driven, and keyed to something being 
the tallest, sharpest (protrusion), object. This is why quads, which are 
"boxy", have the reputation of being "low noise". As a matter of fact, the 
quad was popularized by use at HCJB to eliminate corona.

There are often isolated circumstances without clear understanding that seem 
to point in one direction, so I tend to go with something that fits what 
almost always is observed. The overwhelming evidence points to charge 
gradient between the sky or atmosphere and earth, and not little charged 
particles hitting out antennas and making a tiny spark. Even the noise pitch 
is almost always unrelated to quantity of particles.

73 Tom