Topband: AM broadcast tower and 160m dxpedition

[Tom W8JI]

> Half wave verticals have been very disappointing to me over the years when 
> I had the tall BC towers in my backyard to play with after midnight on 
> 160.

I installed a 318 ft insulated base tower in stages and watched the results. 
I felt there was very little difference from 1/4 wave up to about 200 ft or 
so, and then above that I started losing signal under many conditions for 
almost no gain on anything. At 318 ft I lost considerable signal within the 
first 500 miles for no real difference, or actually some loss, out far. When 
I replaced that tower, I never bothered with a base insulator on the new 
one.

The same thing was true in Ohio using BC towers, although that was just load 
them up and try them.

I also remember from years ago how poor W8LT's signal was in one 160 contest 
when they used a 5/8th wave vertical.