Dave_K9NX wrote:
>
>I am in the process of building a two element broadside vertical array for
>40M (which may grow to a 4sq next year) the radial system for each vertical
>is #18 insulated hook-up wire (about 30 per vertical so far). The radials
>cross each other at several points. What is the collected wisdom should I
>leave the radials insulated from each other or should I "bond" them at the
>cross over points?
>
Not sure - but whatever you do, make all the sets of radials identical.
G3HCT wrote an article for RadCom last year which showed how important
that can be in getting a really good F/B ratio in all switched
directions.
>In looking at some older texts I notice It used to be popular to have a
>small ground rod at the far end of each radial. This practice seems to have
>vanished from vogue in recent years. Was there any known measurable
>advantage (or disadvantage) to doing this? Have folks just stopped doing
>this because of the work involved? Or was this one of those "old Elmer's"
>stories that was gratefully debunked and discontinued?
An article by Jerry Sevick, W2FMI in QST for April 1978 seemed to show
that the ground rods at the ends only make a significant difference if
the radials are very short... which is pretty much as you'd expect.
73 from Ian G3SEK Editor, 'The VHF/UHF DX Book'
'In Practice' columnist for RadCom (RSGB)
http://www.ifwtech.demon.co.uk/g3sek
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