[TowerTalk] 80m vertical ideas / questions

[N1BUG]

I have received a large number of responses both on and off list. Thanks 
everyone!

Several mentioned adding an 80m wire vertical alongside the 160m shunt 
fed tower, series feeding the 80m and using the existing radials. That 
idea has much appeal as a space and work saver if it can be made to 
work. I tried it several years ago and it didn't go well. The MFJ 
antenna analyzer said R was 1 or 2 ohms and I got nowhere trying to 
match it. I suspected it wouldn't radiate well if I did get it matched 
and gave up. I don't know why it did that, but it can only be 
interaction with the grounded tower. The antenna configuration has since 
changed on that tower so I will try that again.

I've considered adding another shunt feed to the tower for 80m but am 
not sure it is worth the effort. At one point I did have the single 
shunt feed on that tower working on both 160 and 80. It was weird in 
that all I had to do was switch out some fixed capacitors for 80! Pure 
luck. It worked great on 160 but was a poor DX antenna on 80. The tower 
was electrically just a bit under a half wavelength on 80 at the time. I 
would have to check but I suspect it is now electrically more than a 
half wavelength.

One or more half wave slopers off one of my existing towers was 
mentioned several times. I don't rule that out entirely but I am trying 
very hard to avoid more wires and anchor points. I have so many already 
and I am trying to save some space in case I want to put a VHF or UHF 
EME array in somewhere in the future. I'm on a mission to eliminate wire 
antennas and additional guyed structures partly for that reason.

As far as my original idea, I really cannot imagine 30' of Rohn 25 with 
a 35' stinger on top falling over or being damaged by our weather. As 
far as my concern about bolt hole elongation, worst case if it turns out 
to be a problem I suppose I could weld the leg joints!? If I go this 
route I have no intention of hinging the base but I would provide a 
means of attaching temporary guys when I needed to climb it.

I'm still thinking and looking over some of the many ideas in response 
to this.

My basic problem is I am always stretching the limits of space and 
budget to the breaking point. I understand only too well overcrowding of 
antennas becomes a performance issue. I just strive to get things to 
work as well as I can with what I have.

Happy New Year to all

Paul N1BUG