I'd be interested to know how you make the joints, then add joints to joints,
then...doesn't it get a bit lumpy? Do you solder or crimp or nuts and bolts,
joints in three at a time...?
David G3UNA
> On 12/11/2022 16:41 Grant Saviers wrote:
>
>
> The 34 ohms is the sum of Rr (antenna
I took my inspiration for the one turn counterpoise idea from HF Antenna For
All Locations page 155, Fig 11.9(m).
David G3UNA
> On 09 January 2022 at 17:09 CUTTER DAVID via Topband
> wrote:
>
>
> Thanks, Rick.
>
> My particular circumstances limit me to a sma
they shade
the ground underneath might be worth a try. Compressing things always seems to
limit bandwidth, so, that's something to be wary of.
David G3UNA
> On 09 January 2022 at 16:22 "Richard (Rick) Karlquist"
> wrote:
>
>
>
> On 1/9/2022 4:51 AM, CUTTER DAVID v
Hi Rob
I see copper prices have doubled in the last year.
My intention is to compare and contrast the cost and performance of short
verticals over a large field of ground radials v the very modest amount of wire
required for the FCP. In Guy's article
Rob
I recall a discussion on here some years ago which proposed that, whilst being
an amazing antenna for top band, if you could achieve it, the broadcast model
was not necessarily the best use of resources for amateur purposes, on the
basis that broadcasters are mainly interested in ground
My favourite wire is enameled copper (magnet wire). It needs to be stretched
first but is the slipperest wire you'll ever come across and never tangles. I
pass it through a large polypropylene egg insulator for 100% no-snag
arrangement and cannot freeze up.
I posted this last week but it
I discussed the antenna with him at Visalia and I picked up a leaflet. He told
me that he wanted to patent it but I pointed out that it was in the Moxon book
HF Antennas For All Locations 1982, ie public knowledge. I have built several
like it just for fun and they work. It's basically an
There are some interesting things going on in the Cross Country Wireless group
with phased loops. Look for Simon about half way down this link:
https://groups.io/g/CrossCountryWireless/topic/79362931#7537
He tells us that he works across the pond on his multi-turn transmit loop and
now has 4
Mark
I like that idea the best. I would tie the parts together with a long piece of
rot-proof cord so they don't get lost.
David G3UNA/G6CP
> On 03 January 2021 at 16:38 Mark Robinson wrote:
>
>
> I use 1/4 inch AMP spade connectors , male and female as a breakaway
> point on my open wire
My friend G4IUF uses a plain dipole on top band and it's anything but straight
or high: it mostly meanders around his garden going up and down, along fences
up a tree, out to the front gate, etc. He has a successful record on the band
up there in the low hundreds. I marvel at his ability to
I read a comment some while ago that our impressions of what is required for
our low bands is distorted by the original works done in the 30s for medium
wave broadcast transmitters in USA, in that, broadcast needs are different
because they are servicing a "local" population and thus need a
Roger
Thanks, I had the same idea but I am concerned about the point pressure at the
end of the scaffold pole on the inside of the Spiderpole, since on raising and
lowering that would be at its extreme.I came to the conclusion of using a
"soft" buffer to spread the contact pressure. I
Further to that scheme, is there a sound way to join a Spider pole to a
scaffold pole? The cost change from 18m Spider to the next sizes up is quite a
jump, but I've often thought an alloy scaffold pole at the base would be worth
the effort if I had a decent way to join them. I can raise the
I've seen Cat 5 and 6 cable used up to 20MHz on one pair, power on another and
data on a third, perhaps switching on a fourth pair. I know this works for
distances of at least 20 metres and I wonder if it would be good at LF for 10
times that distance. It's also very tough and modestly priced
A friend over here told me he was bothered by QRM on 1822 last week and we
don't have any harmonically related MW stations that could cause that, so, it
could be the same source.
David G3UNA/G6CP
> On 18 December 2019 at 15:09 David Olean wrote:
>
>
> I think I did. I could hear voices and a
Either let the box breath and provide drain holes, or seal it tight and fit a
desiccant. Conformal coating to protect circuitry is rare except in very
sensitive/expensive products.
David G3UNA/G6CP
> On 29 October 2019 at 22:08 David Olean wrote:
>
>
> Hi Mike
>
> I would think that you
I shall be trying 2 modest flags at right-angles. I will switch polarities to
obtain 4-quadrant reception into a K3S dual receiver in diversity mode. It's
not all about gain or beamwidth but what the brain can work on to separate the
signals and noise. In the absence of acreage this should do
Kevin
This might help on a small lot: I am very fortunate to have a dual rx K3S and I
am planning to use 2 flags at right-angles in the corner of the field I've been
loaned. Being in the bushes and at modest height they cannot be seen and with
relays to change phase of each I hope to get 4
If it hasn't already been mentioned, here's something to watch:
https://www.youtube.com/watch?v=fyZR9uMBnIo all about receive antennas.
about an hour in W3LPL gets into more detail about high and low Z circle
arrays. I'm definitely thinking about this on a neighbour's land.
David
Thanks, Guy for clarifying the re-radiation issue. I had thoughts of the other
way around as well, ie, the inverted L (or other tuned antenna) affecting the
rx antennas. Breaking the dual band L somewhere to negate this effect might be
more important. To that end I thought of simply switching
Guy
Slightly OT, but how do you deal with re-radiation from your inverted L?
I'm about to erect one of your inverted L on FCP and my rx loops are about 50m
away in the other corner of the field. Is that far enough?
David G3UNA/G6CP
> On 24 July 2019 at 07:13 Guy Olinger K2AV wrote:
>
>
> I
The usual solution is to do your best. I am fortunate that I can erect the FCP
at 3m away from bushes and trees, but I doubt if I would notice a drop of a few
feet other than tuning.
David G3UNA-G6CP
> On 09 June 2019 at 19:04 Richard McLachlan wrote:
>
>
> Can anybody who has put one of
Hi Rick
How do you find your inverted L on receive, or do you have separate rx antennas?
David G3UNA/G6CP
> On 05 May 2019 at 00:55 Rick ve3mm wrote:
>
>
> My lot is 60x100 ft with a swimming pool taking up most of the backyard. I
> managed to squeeze in an 160 m inv L running from the back
I've had lots of PL259s (probably cheap ones) that have non-matching threads.
David G3UNA/G6CP
> On 05 December 2018 at 21:52 James Lee wrote:
>
>
> The Pasternack offerings are pretty expensive, especially given that no
> silver is present! They are listed at about 11 bucks each unless I
Barenco in the UK make an excellent product line.
David G3UNA/G6CP
> On 05 December 2018 at 18:20 Martin mailto:dm...@t-online.de > wrote:
>
>
> You can buy from a reliable seller in Germany.
>
> I've been using them for years and replaced all uhf-connectors with
> them. They are
Jim
This will be an issue for me shortly: which part of your tx antenna do you
switch for de-tuning? I'm building an inverted L on an FCP and I'm looking for
the most convenient place, physically and RF-wise.
David G3UNA/G6CP
> On 28 November 2018 at 13:18 John Kaufmann
I wonder if touch-sensitive paddles might suit better. I don't like them but
you never know.
David G3UNA-G6CP
>
> On 27 October 2018 at 19:08 John Randall via Topband
> wrote:
>
> I have moved home now and am awaiting planning permission to erect some
> poles in the garden, but
Just a thought: I'm not quite sure of your arrangement, but if the analyser is
not grounded it will pick up common mode current and distort the readings; hand
holding is also affected. This has confused me a lot in the past. Now I use a
clip and tent stake in the ground and that stabilises the
Drifting the thread slightly: I read an article recently regarding 2 loops of
15ft square separated by 15ft which the author called Loop On Ground, LOG. He
claimed good results on receive over a period of a year. It was very low gain
but had directional properties and was said to be quiet.
Along the same lines, I'm always amazed that folks with 4 squares state they
have such and such gain, f/b ratio and so forth but when modeled with the other
hardware in the field there's quite a poor response. I would like to read of
anyone who has done actual measurements of these properties,
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