Topband: Radials question

[Rob Atkinson]

> was wondering couple things. If I make a full quarter wave vertical WIRE
>in tree 65 feet tall and see DX Engineering verticals claim 65 foot tall
>but wider bandwidth. What is their secret or just advertisement?

I don't know the DX Eng. product.  Usually "wider bandwidth" means
flatter vswr curve at the load.  There are right and wrong ways to
achieve this.  Right:  wider driven radiator.  Wrong:  few radials or
no radials at all.  There can also be some kind of hocus pocus
matching network at the feed point, and that can be okay, or a power
wasting circuit depending on how it is done.  I'd go with vertical
wire to the tree branch and ground system and save money.  It will
work just as well or better if you use a lot of radials, but because
it will be efficient, it will not have a flat vswr curve.  You'll need
a matching network in the system somewhere.  If you can elevate the
radials at 10 feet or higher, you may do okay with four of them
equidistant and 1/4 wave long.  On or below grade you need at least 60
for best performance.


 > Second question, I understand more radials make vertical better, but what
>happens if one side half or one third the length radials due to space in
>yard are shorter by 20 to 30 foot? Is it noticeable enough to buy a

It probably won't be noticeable if you put down a lot of radials.


>  Third and last question, can some of the radials, quarter of them,
>overlap with radials of another antenna (160M mono vertical Gladiator
>antenna)? Would it affect the performance noticeable.

It won't have any effect on performance.  Do you have any metal
structures near your vertical antennas?  Aluminum siding, metal
sheds....you should bond these with brass clamps to copper strap and
run that strap back to your ground system common point.

73

Rob
K5UJ