Richard Clark wrote in message . ..
On Thu, 20 May 2004 08:14:18 -0700, "Just Another Opinion"
wrote:

Richard, Thierry and the original poster I repeat:

Repetition is both tedious and changes nothing.

The R7 is NOT a quarter wave vertical -- it is a half wave end
fed antenna.

Mantras soothe the soul certainly.

A quarter wave radiator needs a ground plane or radials to work against for
sure -- but Cushcraft sez a half wave antenna doesn't need radials as it is
like a horizontal dipole turned vertical and end fed (high impedance) rather
than center fed.

Not needing and prohibiting are not the same thing.

I suggest you read and study the following:

The Cushcraft manual it explicitly states "The
R7 should not be attached to a ground radial system".
URL: http://www.cushcraft.com/support/pdf/r7.pdf

Yeah, and page one:
"System Grounding"

One radial good.
More radial bad.
Yeah, sure.

In fact a word search against the quote above returns 0 hits. So much
for explicit statements and what "should" be read. I note the links
below have the same breathless nature, which is to say a lot of air.


Richard,

I don't know the answer to the main issue of this thread. I just
don't know enough about antennas to speak as an expert. However, as a
point of fact, the R7 manual does state on page 1 under the section
titled "Location":

'Although the R7 will operate in almost any location, it will perform
best if it is mounted vertically and located in the clear away from
surrounding objects such as buildings, trees, powerlines, towers, guy
wires, antennas and metallic objects. The R7 should not be attached
to a ground radial system. Failure to heed these points will possibly
degrade performance, detune the antenna and increase VSWR".

When I clicked on the above link, a PDF file was opened. It appears
that the manual was scanned and stored in PDF. In this case, no text
search would be successful.

FWIW, when I added radials to my R7 I was unable to tune it properly
on all the bands. Once the radials were removed I was able to tune it
up without problems.

Thanks,

Rick, K6RJ

On 21 May 2004 10:02:45 -0700, (Rick, K6RJ) wrote:

I don't know the answer to the main issue of this thread. I just
don't know enough about antennas to speak as an expert. However, as a
point of fact, the R7 manual does state on page 1 under the section
titled "Location":

Hi Rick,

Thank you for the follow-up. You are correct, and yes the pdf is a
poor, unsearchable copy as evidenced by your observations offered.

As far as this thread goes, I've seen testimony that it works/doesn't
work with radials - both ways. Such is the value of testimonials
where you can find any answer to suit any occasion.

I've seen testimonial "proof" that an eh works better than a standard
quarterwave, wherein the data clearly proved it didn't. The
testimonials dismissed the data (their own) as irrelevant.
Testimonial is fine and is occasionally called for. Testimonial as
proof is worthless.

I've offered data to this point of a "prohibition" on using radials.
The difference between 120 quarterwave or halfwave radials compared to
one short "counterpoise" barely tipped the meter at 1dB on the
performance side of the ledger. As for matching, I averred that
tuning may be impacted (I cannot imagine how it could be otherwise).
THAT is within the provence of Amateur radio service as a minimum
technical skill. THIS is a technical forum where design and data is
offered for examination. The remaining correspondence is confined to
the slow lane or the shoulder when a rhetorical axle is broken.

Frankly, this "prohibition" of no radials is more a design mandate,
not a papal bull. The site offered where we can find the actual
components of the "black box" displayed and laid out schematic style
offers an equal opportunity to redesign to allow radials. This
apparently is not within the skill-set of many, or arguably even
desired; however, it is not impossible (nor particularly difficult).

To this last point. I would offer that most of the interesting
correspondence (that isn't simply entertainment quality) is composed
of rather academic interests. Some of it is impractical in the
extreme and as absurd as fractals. More of it barely offers a
difference that would twitch an S Meter, or a Power meter. This does
not mean it lacks merit in its discussion because, let's face it, a
forum is built and survives on the vigor of debate. Clearly no one is
going to (legitimately) re-invent the dipole, so topics become rather
obtuse.

73's
Richard Clark, KB7QHC