Sorry for the late reply - Im playing catch up after a weeks lumberjacking (I kid you not) -
Im not sure I agree with you at all reference the effectiveness of loops in trees. I certainly didnt struggle either - In fact it was so easy I couldnt believe the results at first - Certainly "Loops in Trees (c)" are not perfect, but Im not in the isotropic realms of perfect illumination so I do my best with what I got.- I just flogged my Rhon 45 towers.
Looking at the derived/realized ERP/field strength figures for my Oklahoma and Alaskan loops both with an area of around 640 sq metres - and based on ground wave measurement in near mid and far range, I dont believe I was losing a lot at all ("at all" in relative terms).
In the main lobe I was running around 1-3W ERP and given my circumstances I dont think it was a poor peformer given I had zero/nada/zilch change of putting anything up above tree height and it will be the same at WE2XPQ.
Im a tree hugger as a matter of necessity as everything else would become a target for the rougue weekend flyers dropping out of the sky at my 200m away landing strip.
back to the loop
500W 137kHz Daytime Ground wave CW readable in 1.8Khz BW/IC706 was over >650miles from a mobile and magmounted probe which I dont believe is too shabby, and it got to ZL too, and AQC/LDO 6NM got back the other way (Im trying not to brag, but youll see the point)
Its horses for courses and as others have pointed out earlier we havent seen a large amount of commercial or military LF tx loop in service designs (save for one I know of near Puerto Limon Costa Rica) - But what I do know that given the results of Wild Bills work and real time results of LF "Loops in Trees (c)" that the military are taking another look at what can be achieved and thats all down to experimentation by all this mob and our Colonial friends. And what fun too - talk about a steep learning curve dealing with >50amps of antennae current!
Regards
Laurence - Tianjin China
We2Xpq Wasilla AK
ps I dont think Im a serious operator but there again I have a sense of humor too, at times.
> From: [email protected]
> To: [email protected]
> Date: Thu, 20 Aug 2009 18:29:09 +0100
> Subject: LF: Re: Re: Tree noise
>
> Like I have said in the past several times I am surprised how many LF/MF
> operators have loops strung from tree branches and in amongst trees and
> claim they are perfect, especially those in the USA.
> Most of the rf is being absorbed by the trees, perhaps a little escapes.
> Compared to loops little and large sited out in the clear they are poor
> performers at LF/MF
> Serious LF/MF operators should look for a QTH out in the clear avoiding
> serious obstacles like trees and close in buildings. Why struggle to
> reinvent the wheel when one has options like CABLE, MOBILE PHONES AND THE
> INTERNET to surf and chase LL DX.
>
> g3kev
>
>
> ----- Original Message -----
> From: "Mike Underhill" <[email protected]>
> To: <[email protected]>
> Sent: Thursday, August 20, 2009 11:44 AM
> Subject: LF: Re: Tree noise
>
>
> > Dennis (DL6NVC)
> > Please could you try your loop away from the tree. Preferably more than 2
> > metres. I have found severe bio-electric(?) noise from trees from 3.5 to
> > 500MHz.using loops, whips and UHF Yagis. The noise drops to almost zero
> > if
> > the tree ambient temperature is below about zero Celsius.
> > Mike - G3LHZ
> >
> > ----- Original Message -----
> > From: "Dennis" <[email protected]>
> > To: <[email protected]>
> > Sent: Wednesday, August 19, 2009 2:03 PM
> > Subject: LF: Re: 500kHz qrg range* THANKS!
> >
> >
> >>
> >>> 2. Most of the time there is a terrible broadband noise present in my
> >>> home location, which blocks everything below 14MHz and even degrades
> >>> Polskie Radio I on 225kHz and BBC4 198kHz (with the rx loop outside the
> >>> house in a tree). That's the reason why I did not report any reception
> >>> on
> >>> 500kHz in the last weeks. There simply wasn't anything to receive...
> >>> Although in a few kHz bandwidth this broadband noise of course does not
> >>> equal the fieldstrengh of a local broadcast station, the broader the
> >>> filter, the higher the level, unneccesary loading the mixer.
> >>
> >> vy73
> >> Dennis
> >> DL6NVC
> >>
> >>
> >>
> >>
> >>
> >>
> >>
> >>
> >> --
> >> Neu: GMX Doppel-FLAT mit Internet-Flatrate + Telefon-Flatrate
> >> für nur 19,99 Euro/mtl.!* http://portal.gmx.net/de/go/dsl02
> >>
> >>
> >
> >
>
>
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