On 3rd November, Rick wrote:
"...I have only 16 65 ft radials and I know I need more..."
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Hi Rick,
Taking another look at Table 1 on page 3.10 of the ARRL "ANTENNA HANDBOOK",
with radials 1/8-wave long --- such as what you have there --- a diminishing
rate of returns on your investment, in terms of both time & copper, would
start at the 24 radial benchmark...
Positive returns on adding more radials of that specific length beyond that
number would make the effort & costs hardly worthwhile --- according to that
source...
On the other hand, ON4UN states in his book (page 9.14) that:
"For short radials (0.137-wave), there is negligible benefit in having more
than 15 radials."
Take your pick.
In either case, it would appear that the next step you might have to take in
order to improve things realistically would be to add MORE radials, but at
the same time time, LONGER ones...yet, there always remains the nagging
factor of EXTRA COSTS involved, as ON4UN puts it so very well:
"For radial lengths of 0.274-wave and greater, continuous improvement is
seen up to 60 radials. Note that doubling the number and doubling the length
of radials from the above case (i.e. 15 short radials of 0.137-wave) ONLY
GAINS 1 DB GREATER FIELD STRENGTH, WITH *FOUR TIMES* THE TOTAL AMOUNT OF
WIRE." (all emphases mine).
I have a personal interest in all these discussions, Rick, because my
3-element phased "L" array has 24 0.125-wave radials beneath each: if I was
to take the "...60 radials 1/4-wave long" route, my expenses would be
effectively tripled!
I guess I'll simply make-do with what I have here --- for now --- and keep
my eyes peeled for wire bargains in the future, because the next step up for
me will most certainly be a "doozey" both in terms of time, AND money...
~73~ Eddy VE3CUI - VE3XZ
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