Appologies for my delayed response. Cleaning out my inbox.
There are two aspects of the following story.
First, the G5RV pattern which on 30M is a figure 8 pattern of
approximately 50 degrees beamwidth due to it's acting as
two half-waves in phase on 30M. Most likely the G5RV pattern
was not favoring the target station.
Second, radiation from the non-resonant driven elements of
the C3 tribander.
Since the C3 has a split dipole feed, there is no "filtering" due
to a tuned matching system. Yes, it is mismatched, but will
radiate power that is applied. Using a tuner will enable more
power to be coupled to the non-resonant driven element. Yes,
there will be increased transmission line loss due to the
mismatch between the antenna feed impedance and the coax.
And there will be additional inefficiency (<3 dB) on 30M due to the
fact that the longest driven element is still less than 1/2 wavelength
(approximately 70% ).
BUT, a non-resonant dipole WILL effectively radiate the power
that is coupled to it. One of my favorite antennas is a 20M
dipole fed with ladderline and a Johnson Matchbox. It gives
a figure 8 pattern on 10, 12, 15, 17, 20, and 30 Meters, varying
in beamwidth (inversely in frequency) from 50 to 90 degrees.
This reminds me of my early days on the WARC bands when I
worked an African station on 15M who was in a country that I
needed on the WARC bands. All of his antennas had been
damaged in a storm except for the 15M dipole he was using
with his TS-830.
After an hour long ragchew I persuaded him to try using his
15M dipole on 17M, tuning the pi-network for maximum output
on 17M. We worked with excellent signals. It was well past
his sunset but my propagation program showed a reasonably
high MUF at his QTH since it was summer at his QTH and MUFs
tend to rise slowly and remain high after dark in summer so we
decided to try 12M. Sure enough, the band was still open,
although signals were weaker.
Following these two successes, he was so excited that he wanted
to see if the 15M dipole would work on 30M, where it is only half-size.
Once again we were pleasantly surprised and he remained on 30M
for another hour, dispensing the first ever 30M contacts from his country
.
At half size, the reduced size accounts for several dB less efficienty,
but
it did work. The G5RV represents 70% of a half-wavelength on it's
lowest frequency which is more efficient, probably on the order of 2 to
3 dB down from a full size dipole.
de Tom N4KG
.............................
On Tue, 13 Oct 1998 13:28:39 -0400 Bijou Bubba
<al.jaras@meriden.k12.ct.us> writes:
>
>Yesterday I worked a UA0AZ, zone 18, on 30M. I wasa surprised by the
>contact since I had my C3 in line and not thge G5RV I always use.
>Needless to say I received a 579 from ALEX and after the contact I
>realized the error I had made. Goiong to the G5RV caused a severe
>attenuation to Alex's signal and switching from the C3 to the G5RV
>did
>indocate a much stronger s meter reading like 4 s units. I assume that
>the C3 was functioning adversely but because of directivity as
>compared
>to my G5RV was able to pull Alex in better. Has anyone out there used
>the C3 on 30M with any success??
>I am interested in comments concerning this.
>
>Thanks ALL
>
>de AL /NA1I
>
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