[Lowfer] Antennas (WAS: Lowfer WH2XXP to NE IL)

[John Hamer]

Zach,

I have a 6 foot balanced loop with the K0lr unbalanced loop pre-amp with
remote tuning. I have the circuit modified slightly to make it work with a
balanced loop. A balanced pre-amp would obviously be better. The loop was
originally unbalanced, and it works much much better in a balanced
configuration. When I converted it to a balanced loop, it became much more
directional and I could block the noise from my house and the power lines
out.

I have received all the east coast lowfers with it. I am in South Carolina,
so most of them are pretty far away. The balanced loop is directional
enough that I can null out my lowfer transmitter enough to still receive
lowfers from the north east US. They are maybe 150-200 feet apart.

When I got serious about trying to get that loop working, I built a little
oscillator circuit / antenna and put it like 50 feet away from my antenna.
I kept lowering the output from it until it would get lost in the noise,
then I would mess with things to try to get where I could see it again. I'm
pretty confident I am receiving the noise floor with its current setup and
if any signal is in my yard I can see it. My largest source of noise was
actually the computer I was using to monitor the loop. I tried all the
computers in my house and found an old E-machine was the quietest. So, that
is now my computer used just for monitoring lowfers. It's worth playing
around with grounding also. Try grounding one or both sides of your coax
running to your loop. If you run a balanced loop, a good ground by the loop
is def important.

One other thing I did, which I can't remember if it made a difference, was
impedance match the output from the K0lr pre-amp to my feedline, which is
75ohm coax. I don't remember what the actual impedance output of the
pre-amp was, but I don't think it was 50 ohms like I would have expected.

I have used a vertical like N800U described when I used to look for NDB's
and it worked really well without a pre-amp. I have not tried to look for
lowfers with that setup.

John Hamer
Lowfer JH

On Mon, Nov 14, 2022 at 10:00 AM Zack Widup <w9sz.zack at gmail.com> wrote:

> I'd like to know what you folks are using for antennas and preamps to
> receive the signals in the watering hole and other frequencies. I have been
> having an awful time with antennas for that frequency range. I have a 5
> foot square loop with 20 turns of wire tapped at 3, 5, 10 and 15 turns in
> the back yard. It has failed miserably. Mostly what I get is noise. I have
> a feeling that the noise is coming from a DSL line that passes almost
> overhead. I have tried several preamps, including the K0LR and LZ1AQ
> preamps. None of those seem to make a difference. I have tried receiving
> with a TS-850SAT and  FunCube dongle, which both cover LF.
>
> I just built a smaller antenna this weekend, a one turn loop one meter in
> diameter, with the LZ1AQ preamp. This preamp was designed for that
> particular size of antenna. I put it in the front yard, far away from any
> wires. It performs remarkably well, much better than the loop in the back
> yard. But I still don't detect any signals in the watering hole.
>
> I also have an AMRAD e-probe antenna that I've been wanting to put up. But
> I need to borrow an extension ladder to get to rooftop level on my house
> and also need to borrow transportation to move the ladder (a Saturn Ion is
> not going to work).  :-)  I'm probably only going to be able to get it up
> about 15 feet.
>
> But what are others using?
>
> 73, Zack W9SZ
>
> On Mon, Nov 14, 2022 at 7:38 AM Garry <k3siw at sbcglobal.net> wrote:
>
> > No luck monitoring 181.82 kHz over night so switched to the watering
> > hole before local sunrise. Using QRSS60 saw only the merest traces from
> > TAG but WH2XXP was in there a bit so changed to QRSS30 and caught a full
> > call sign (with some imagination) just before local sunrise at 1242Z.
> > Not bad for a 2342 km path.
> >
> > 73, Garry, K3SIW, EN52ta, Elgin, IL
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