[TowerTalk] 160M Antenna puzzlement

[Jim Brown]

On 12/19/2021 10:55 AM, Jeff Blaine wrote:
> For 160 something around 8+ turns & type-31 are the "right" rule of 
> thumb answers.

Based on my research, a lot more turns. http://k9yc.com/2018Cookbook.pdf

Pete has received lots of good advice in this thread. I'll add this. 
Base loading is a bad thing, because it places inductance at the point 
in the antenna that carries the most current, and should be doing the 
radiating. Better to remember that SWR is NOT a measure of antenna 
performance, that as Jeff has noted, feedline loss is pretty low on 
160M, and that what matters for moderate values of SWR most is whether 
you amp can put power into it with the help of a tuner. And if 
practical, I'd replace that length of RG8X with something the size of 
RG8. OTOH, doubling the number of radials, realizing that length of 
on-ground radials is not critical, would probably help TX signal more 
than replacing that coax, and would change the feedpoint Z a bit.

While adding horizontal length is technically a great idea, sometimes 
that isn't practical. I like Jeff's suggestion of an L-network at the 
feedpoint, but the design requires either a lot of cut and try, or a 
sweep of the feedpoint Z with a good vector analyzer whose data can be 
ported to design software like SimSmith. I'll bet that Pete has 
neighbors who can do that. And if Pete can send me a suitable sweep, I'd 
be happy to do a design.

73, Jim K9YC