So here's a bit more of my thinking: my main goal is improved RX performance
so does current distribution, presumably a TX consideration, really matter?
The loop is recognized as a low noise antenna so increasing its size should
only improve SNR. No?
Then the other comparison I draw is to small RX loops, which also are widely
acknowledged as effective RX antennas. So what if we make the small loop big.
Really big. Full wavelength big. Is it still effective as a RX antenna?
Rudy N2WQ
Sent using a tiny keyboard. Please excuse brevity, typos, or inappropriate
autocorrect.
> On Dec 28, 2014, at 1:21 PM, David Gilbert <xdavid@cis-broadband.com> wrote:
>
>
> In general, there is nothing beneficial about simply having more wire as
> long as what you already have is electrically efficient. Yes, there are some
> configurations where "more wire" can help ... a loop high enough off the
> ground has a db or so gain over a dipole at the same average height, a
> curtain array has gain, a dipole extended in length with capacitance has a
> bit of gain, etc ... but in your case your additional wire simply moves more
> of the current distribution closer to ground, thereby raising your
> takeoff/receive angle. It might be a bit quieter, but not necessarily in a
> good way ... in my opinion.
>
> If you want to hear better toward Europe, maybe you could try running a rope
> westward off your tower to an anchor point as far from the tower as you can
> get it, and then hang a reflector wire off that rope about 100 feet away from
> the tower. The reflector would be pretty close to the ground, but might ...
> might ... offer some benefit. Slight improvement in forward gain, modest
> improvement in rearward rejection, possibly decent sideward rejection, very
> slight lowering of takeoff angle. If probably would alter your current
> tuning, but might be worth a try.
>
> 73,
> Dave AB7E
>
>
>
>> On 12/28/2014 7:35 AM, Rudy Bakalov wrote:
>> I actually do have the exact same setup- an inv-V at roughly 90' with both
>> ends sloping a couple of hundred feet away from the tower. The apex is more
>> likely ~120 degrees than 90. It works really well (skimmer data shows actual
>> performance much better than theoretical), but I was wondering if I can
>> improve on it, particularly on receive where I feel I don't hear well
>> enough. I guess my question is "if a piece of wire of certain length works
>> really well, what happens if I double the length of the wire".
>>
>> Rudy N2WQ
>>
>> I'm curious what you desire to achieve from such an antenna. It's not
>> likely to be an improvement over what you already have.
>>
>> A few years ago, before I was able to put up my current tower and yagis,
>> I suspended a 40m diamond-shaped loop from a 55 foot tall pole ...
>> sloped toward Europe from here in Arizona and fed at the bottom apex.
>> It worked OK, mostly because I live on a steep hillside facing Europe,
>> but in my opinion it didn't offer anything special other than it was
>> also possible to use it on other bands with a decent tuner. Keep in
>> mind that unless you feed it at one side for vertical polarization that
>> half your current distribution is going to be pretty close to the ground.
>>
>> In my opinion, you'd be better off stringing an Inverted-V from the top
>> of your tower if you want something horizontally polarized to complement
>> your existing verticals.
>>
>> 73,
>> Dave AB7E
>
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