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Well Done That Man!

There is a key point in comparing active loops by off-air signals that
now you can appreciate. If you are in an average or bad urban setting
then the noise floor is so high that you can't hear or assess the noise
floor of the loops you are comparing. The only way is by using dummy
loops and good signal generators in a screened environment - something
that most people on You Tube don't do so their comparisons in noisy
places cannot sort good from bad. But now you can tell !

The best reception that I have seen was at a BBC location, they had long
Beverages in all directions that each had their own distribution amps.
Each listening position has it's own very nice RX and a great big
antenna switch. Their stock demo was to tune to a quiet-ish spot on MW.
Turning the knob then revealed various local stations in the UK and
Europe, the last position? was a provincial? broadcast from China - that
was on a Winter afternoon before dusk.? Very nice to drive a receiver
from a directional antenna system! I did emulate that with six Beverages
in a Contest group. Being able to operate by rotating a directional
antenna is a totally different way of operating radio, one tasted never
forgotten.

It might now be worth thinking about some spaced loops, you can get some
very nice directivity from 4 to 6 broadband loops with delay lines to
beam form.? It is helpful to think of the delay from one loop to the
other, don't think in phase but time. The delay time approach allows the
performance to be more even over a wide frequency range. Using active
loops or e-field antennas also has the huge advantage of zero
interaction between the elements. Serious people have been using 6-10
element circular arrays for many years now, you get the multi Beverage
like performance in a much smaller space but you do use a lot of coax
and land in a very low visibility way!

Now that you have the great opportunity I would strongly recommend?
ON4UN's book "Low Band DX'ing" from the Really Small Gas Board, It is
the best of it's kind and has a lot of very good Antenna stuff. You
might also consider something very low profile that works automatically
in the background and gives you continuous world wide and band wide
data, a WSPR station. An SDR like a Red Pitaya allows you to log 8
channels automatically and report back to the server via a LAN. Although
you can also watch everything via the "wspr.rocks" app.? The "top
spotters " section gives a score to spotters, currently I'm around 120th
in the table, that's on an active loop 10m from my house and only four
channels of RX. Bound to drop out of the top 200 now.

If you have a big smart TV then it's very nice to show a World map with
all of your spots across all of the bands to visitors, it also shows
when and where the bands are open. It's a good way of telling people
what radio is about and impressing them? ( it impresses me too!) You can
get the Map on wsprnet. org but the wspr.rocks map is much quicker and
has some really great features. I often advocate using wspr reports as
test gear, the SNR numbers are real measurements not deception meter
guesses and you can compare your reports with others- or in your new
situation - how much better yours are against the people left behind!
But it's a very useful free tool, if you transmit wspr then you have
hoards of spotters that can tell you how changes at your end alters
their reception.

Your new QTH is very appropriate, it is in the district called South Hams!

best 73, Alan G8LCO


On 11/02/2023 14:35, Simon wrote:
> Hi Alan
>
> Simon g0zen
>
> Have just moved from Dagenham to Bittaford inside the dartmoor national park..
>
> Noise floor on 160-40 dropped from s7 to s1.( occasionally s3) .and thats on the Marconi T tx antenna ( still in progress, as currently only tx on 80m, matching network and 160 coil to be made)
> Similar noise on the trapped 40-80 dipole.
>
> Revelation though are the lz1aq’s amps, crossed parallel loops and switchable delay line, ( 4 directions.) its as though nothing, UNTILL someone transmits, ok maybe s1 on meter but silly good sn ratio.
>
> G0ZEN
>
>
>
>