At 10:19 AM 5/8/98 -0400, Bill Fisher - W4AN wrote:
>> That, combined with the lower radiation
>> angle, should make the 4-square quite superior to a high dipole. Most
>> 4-square owners I've talked to think so.
>
>Well I'm a 4-square owner and I am going to disagree with you to a
>point. This winter I did some comparisons with N4RJ on 80M CW. Val is
>running a inverted-V extended length dipole with the ends pulled slightly
>toward Europe at a height of 165 feet. I'm not sure of the exact length
>of the dipole. Every station that we compared with that night gave Val
>one S-unit advantage over my 4-square. Every station we worked was in
>Europe and Val and I were both running the same power output.
Not surprising -- I ran a quick comparison between some models I have here.
The 4-square has a maximum gain in its favored direction of 5.29 dBi at 26
degrees elevation. A dipole at roughly .6 wl above ground gave 9.29 dBi at
a 25 degree takeoff. Now, I didn't put a lot of effort into trying to make
sure the ground quality was the same, etc., so take these as a rough order
of magnitude, but it's not suprising that Val's extended dipole was louder.
Depending on how much longer his "extended dipole" was, the difference
might be even greater.
>
>However, I seemed to be hearing better than Val (he was using a
>beverage), and I believe I am far superior in all other directions
>especially to Asia.
Again, not surprising. He hears noise from the back as well as from the
front, while the 4-square model shows 16 dB F/B ratio.
>
>I think a high dipole (150' + ) on 80M is a VERY good transmit antenna in
>it's favored directions. Combined with some phased beverages for RX, I
>believe this is better combination than a 4-square to those directions.
>However, the 4-square is very versatile.
And a rotary dipole at that height, even loaded for a reasonable size, will
most likely beat the 4-square in every direction, while not hearing as well
in any of them.
To my mind, horizontal antennas will almost invariably be better for DX if
you can get them at least .6-.75 wl high and if they can be rotated, or you
have enough of them. The ground reflection gain gives you a lot of oomph
more-or-less for free, while the vertical owner is laying down lots of
radials trying to get back to the performance the models say he should have.
73, Pete Smith N4ZR
In wild, wonderful, fairly rare WEST Virginia
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