[Lowfer] Lowfer Digest, Vol 102, Issue 1

[Douglas D. Williams]

Hi Peter. Yes, you are correct that most people orient their loops to null
out interfering signals, as the nulls are sharp and deep.

Receiving loops have long been used at VLF/LF, with good results.

I get tired of seeing people "poo-poo" active whip antennas, as I have
found them to be very good performers at VLF-LF (and above). Some care must
be taken to place them as far as possible from man-made interference
sources, such as most of our homes. Once a good location is found for the
active whip, common mode chokes help to reduce or eliminate interference
from travelling along the coax shield to the antenna.

I have personally had great success with active whip antennas at VLF/LF.

Everyone's situation is different, and we all need to determine what is
best in our own circumstance.

73, Doug KB4OER


On Fri, Aug 2, 2013 at 12:50 PM, Peter Barick <pbarick at niu.edu> wrote:

>
> Hi Doug and all . . .
>
> Interesting your e-probe observations, esp as I've never used one for
> LowFering.
>
> However one thing I'd like to comment on is use of big ground level rx
> loops.
>
> It's been my experience and that of others in written comment that loops
> are not used a directional antennas like, say, a HF beam or loop is used.
> To the contrary LF loops are best used to null some interfering signal
> (unaffected at my locale) *not* as an enhancing means. This was my
> experience at the watering hole too.
>
> My two un-amp'd, multi-turn loops at about 4 feet off the ground and at 6
> and 10 feet across were generally set E-W and picked up the active ones at
> night thru early mornings on an Argo screen.
>
> --Peter, N Ill
> -----------------------------
> >>> "Douglas D. Williams" <kb4oer at gmail.com> 08/01/13 4:00 PM >>>
>
> Re: e-probes VS loops at LF
>
>
> No idea if this is going out to the correct persons or not, since I have
> subscribed to the digest version of this mailing list until October....
>
> All I can offer is anecdotal evidence, and a few minor observations.
>
> My only experience with a loop at VLF/LF is the Wellbrook LFL-1010, a
> couple of years ago.
>
> It was, IMO, a fine performer. I was impressed at how quiet it was,
> compared to e-probe antennas that I had built myself and commercial units
> such as the L400B.. I received several "Lowfer" signals during the time I
> used it, as well as a few overseas 136 kHz amateur signals. I was not
> impressed by it's performance below 100 kHz.
>
> I compare that to my experience with the Clifton Labs Z1501 active
> "e-probe" antenna.
>
> http://www.cliftonlaboratories.com/z1501_active_antenna.htm
>
> IMO, the 1501 wins, and it is not even close.
>
> All one really has to do is search these threads, and the LWCA web site,
> for my reception reports with the Clifton Labs e-probe.
>
> Perhaps my location has something to do with it. I live on a hill
> ("mountain" to you city folks), in east Tennessee. I live on the top of my
> "hill". My "e-probe" is about 15' above ground level.
>
> As for loops, I find them cumbersome to turn and orient to desired signals.
> I still work 40+ hours a week, and go to bed early, so "live" monitoring of
> LF signals is not usually applicable to my habits.
>
> -Doug KB4OER
>