Just a short note, mainly in reply to Paul, VK3AJJ's posting.
The most important comparison I make when I put up an new 160m antenna is
how well it stacks up against Mike VK6HD's signal with his inverted vee
dipole. From September - April, Mike and I are on the band virtually every
day and I know exactly how well my inverted-U dipole works against his
inverted vee.
My inverted-U dipole works a whole lot better on DX of all distances and
paths (with one exception, previously noted) than any of the myriad of low
angle vertical-type radiators I have tried. Sometimes when I have had a
vertical up, Mike has worked plenty of stuff I can't hear (but worked
nothing that he can't). When my dipole is up, I hear anything Mike can -
and work it, too.
I have put so much time and effort into making verticals work, it almost
makes me weep. Part of the reason I keep trying is that, due to my own good
experiences with verticals from other places, some part of me still doesn't
accept I'm wasting my time.
Maybe I should just go fishing instead. Hey, Carl, are they biting your way?
Vy 73,
Steve, VK6VZ
At 10:16 AM 3/22/98 +1000, you wrote:
>VK6VZ WROTE:
>
>"To give you an idea how poorly verticals perform here on 160m, my friend
>VK6IM has a 70' top loaded vertical (no inductor, just a large capacity hat)
>for 160m with an earth mat of 40-plus full size quarter wave radials under
>it. In most geographical locations, this would leave a low dipole for dead
>on DX - but not here - I work DX easily VK6IM can barely hear/work..."
>
>VK3AJJ writes:
>
>This is not the most scientific of comparisons. I am a firm believer that
>the most important part of the lowband antenna system is the set of ears
>under the headphones. It may well be that vk6im is lounging back in his
>armchair without headphones, with Tchaikovsky playing in the background
>whilst chatting with his wife when listening to the dx (not to mention
>gegraphical and local noise differences). On the flip side your neighbor
>could have "big bertha" humming away in the cellar and the extra 10kw will
>make his vertical / dipole seem very impressive indeed. The only true
>comparison (and even this is not perfect) is to have both test antennas
>available at the one qth for switching by the same operator under near
>identical propagational / local noise conditions.
>
>I often laugh when I read an antenna review in a ham magazine and the
>writer concludes the antenna is a winner when he makes 3 or 4 contacts into
>Europe and is S9 (with no other comparative antenna switching). I could be
>s9 into the ea3sf stacked yagi system on 20m with my mobile whip and as a
>result announce to the world that I have discovered the latest and greatest
>dx-ing antenna.
>
>Another important (non-scientific) factor in Amateur antenna performance is
>ease of construction. It may well be that a perfectly constructed vertical
>array will out perform a dipole every time but probably not if I build
>them!! I am not an engineer and thus the more complex an antenna system
>becomes the more likely it is that I am going to make a mistake which will
>impede its perfortmance. Any moron (yes thas me) can get a dipole antenna
>working efficiently - a vertical system is however far more complicated and
>thus room for efficiency impeding errors is greatly enhanced (thus warping
>later comparison).
>
>Another key "unscientific" question in antenna comparison is what is the
>antenna's purpose?? Is it to work DX or is it to have the highest
>theoretical gain over a comparative antenna. Often a simple but sound
>performing antenna will work more Dx than its sophisticated rival simply
>because the operator is at the radio instead of tinkering with the 4 square
>switching system in the backyard. How often do we hear guys say they will
>be on topband in a big way but because they set their antenna goals to high
>never actually make it on air?? (I of course concede that a lot of these
>guys enjoy the tinkering more than the Dxing and thats fine.)
>
>This post is not intended as a shot at Steve (or VK6IM who I don't know)
>but simply highlights some of the more practical (as opposed to
>theoretical) aspects of antenna comparison.
>
>
>Paul (vk3ajj)
>
>
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>
>
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