[Antennas] Help on 5-BTV radials

[Peter Veach]

> 1. No radials: the mast is not planned to be grounded, I'm afraid
> of severe
> interference at home and neighbors, even if using the ugly 1:1 balun
> recommendation.

I would think about grounding for lightning, if it were me.
Also, if I remember correctly, this antenna -requires- radials to work
properly.
If you do not put up any radials, you will have 'half an antenna'.
Running a wire down to a ground rod would be better than nothing here, and
maybe prevent the house from burning down.
(Grounding for lightning is a whole nuther topic.....)
This is why the so called half wave verticals are popular. They work around
this problem by using a higher impedance feed.



> 2. Attach 10m band radials (shortest, about 8 feet long): I will
> be using a
> lot the antenna on 10m band locally, up to 100km distance radius max.,
> although I'm also interested in the DX use. I'm wondering if the 10m will
> help the multiples (20m, 40m and 80m bands) at all.

Unfortunately, it would not. Longer wavelengths radials may help the shorter
wavelengths, but not the other way around.
Again, anything is better than nothing.


> 3. What frequency on 80m should I tune the antenna (for a newbie,
> like me?)
> apparently the resonator has a tight tolerance on this.

I can't answer this one. DX is near the bottom. Depends on your interest and
license.
I would say listen around the band, and go from there.

> 4. What is the max. recommended SWR for safe transmission without burning
> the equipment? I don't have a tuner, just a SWR meter and will
> transmit max.
> 100W.

Depends on the transmitter, but most people shoot for 2:1 or less.

If you 'ground mount' the antenna, it might be easier for you to get it to
play on the lower bands,
Put out radials as long as you can manage and go with it. However, 10 meters
will work much better mounted up high as you suggested.
The difference being, you will need tuned radials up high, but no so much on
the ground. They really only need to be as long as the antenna is high.
More is always better in the case of a ground mounted vertical.

You might concider using the vertical on 10, and put up a dipole for the
lower bands.
A dipole fed with ladder line to a good tuner will work decent, even if it
is short for the band.
Another thing you could do if hard pressed, is put a choke in the coax 1/4
wavelength down from the vertical antenna for some other band of interest.
Wish I had better news....

Good luck

73

-Pete