Band 1 X aerials

Post by Tweed
Just peering up at the roof tops in Bewdley just now I spotted a band 1 X,
band 3 multi element combination in excellent condition. This led me to
realise that I can’t explain why the band 1 aerial is an X. Can anyone
explain its advantages over a vertical dipole, or the H antenna (which is
presumably a dipole and director).

The H was usually a dipole and reflector.

These pages will explain the X aerial:

http://www.wrightsaerials.tv/aerialphotography/ancient/008.shtml
http://www.wrightsaerials.tv/aerialphotography/ancient/012.shtml
http://www.wrightsaerials.tv/aerialphotography/ancient/024.shtml
http://www.wrightsaerials.tv/aerialphotography/ancient/081.shtml

Bill

Tweed

2021-05-28 19:29:25 UTC

The H was usually a dipole and reflector.
http://www.wrightsaerials.tv/aerialphotography/ancient/008.shtml
http://www.wrightsaerials.tv/aerialphotography/ancient/012.shtml
http://www.wrightsaerials.tv/aerialphotography/ancient/024.shtml
http://www.wrightsaerials.tv/aerialphotography/ancient/081.shtml
Bill

Thanks Bill. I’m sure I still don’t fully understand how one active arm and
the other 3 elements connected to the braid, with the active arm at 45
degrees to the vertical, makes a better aerial.

Liz Tuddenham

2021-05-28 20:47:20 UTC

Thanks Bill. I’m sure I still don’t fully understand how one active
arm and the other 3 elements connected to the braid, with the active arm
at 45 degrees to the vertical, makes a better aerial.

It doesn't make it better, but it is cheaper than an 'H' (with no
horizontal boom), easier to assemble, has less wind resistance and isn't
all that much worse. It also looks a bit less obtrusive.

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(Remove the ".invalid"s and add ".co.uk" to reply)
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Alexander

2021-05-28 21:12:29 UTC

Post by Liz Tuddenham

Post by Tweed
Just peering up at the roof tops in Bewdley just now I spotted a band 1 X,
band 3 multi element combination in excellent condition. This led me to
realise that I canâ?Tt explain why the band 1 aerial is an X. Can anyone
explain its advantages over a vertical dipole, or the H antenna (which is
presumably a dipole and director).

Thanks Bill. Iâ?Tm sure I still donâ?Tt fully understand how one active
arm and the other 3 elements connected to the braid, with the active arm
at 45 degrees to the vertical, makes a better aerial.

It doesn't make it better, but it is cheaper than an 'H' (with no
horizontal boom), easier to assemble, has less wind resistance and isn't
all that much worse. It also looks a bit less obtrusive.

Was there one that looked like an oversized FM dipole, that was attached
to the brick walls of houses; ie. below the roofline?
There are a few of those in my area, and they all look suitably ancient.

williamwright

2021-05-29 00:07:31 UTC

Post by Alexander
Was there one that looked like an oversized FM dipole, that was attached
to the brick walls of houses; ie. below the roofline?
There are a few of those in my area, and they all look suitably ancient.

Here's one with an ITV 'clip on'.
http://www.wrightsaerials.tv/aerialphotography/ancient/033.shtml

Here's one in its entirety.
http://www.wrightsaerials.tv/aerialphotography/ancient/020.shtml

Here's something completely different
http://www.wrightsaerials.tv/aerialphotography/ancient/041.shtml

Bill

Alexander

2021-05-29 00:57:59 UTC

Here's one with an ITV 'clip on'.
http://www.wrightsaerials.tv/aerialphotography/ancient/033.shtml

Definitely that one I've spotted, but without the 'clip on' part, and
with a shorter bracket (so it doesn't stick out from the wall as far).

tony sayer

2021-05-29 14:14:34 UTC

Here's one with an ITV 'clip on'.
http://www.wrightsaerials.tv/aerialphotography/ancient/033.shtml
Here's one in its entirety.
http://www.wrightsaerials.tv/aerialphotography/ancient/020.shtml
Here's something completely different
http://www.wrightsaerials.tv/aerialphotography/ancient/041.shtml
Bill

Don't think I've ever seen one out our way in Cambridge or shire!..

Usually a H type maybe three elements some times of Crystal palace until
we had our local TX channel 2 Horiz..

The only oddity on Band one out this way was around the Newmarket
Suffolk area for BBC 1 from Tacolneston cannel 3 Horiz was a flat "H"
type with its elements made arrow shaped! Don't think Bill has one ofd n
his site anywhere?..

looked like this a bit.. >->

\__\
/ /

--
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Man is least himself when he talks in his own person.

Give him a keyboard, and he will reveal himself.

williamwright

2021-05-30 14:29:16 UTC

Post by tony sayer
The only oddity on Band one out this way was around the Newmarket
Suffolk area for BBC 1 from Tacolneston cannel 3 Horiz was a flat "H"
type with its elements made arrow shaped! Don't think Bill has one ofd n
his site anywhere?..
looked like this a bit.. >->
\__\
/ /

Yes there's one there somewhere. You sent it me.

Bill

Brian Gaff (Sofa)

2021-05-29 08:33:36 UTC

There were straight dipoles yes, Often used line of sight in the direction
they were looking at, They could and did often have reflection and ghosting
and car interference issues though.

The H ones usually had the reflector longer than the dipole of course. I
also saw quite a few of these on 90 degree arms so the pole did not go up
between the elements.
All of these usually needed to be cut to size or bought for the channel
needed as in London the length needed was significantly longer than on the
ones for the rest of the country. 41.5Mhz for the sound 45Mhz for the
vision.
Brian
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Post by Liz Tuddenham

It doesn't make it better, but it is cheaper than an 'H' (with no
horizontal boom), easier to assemble, has less wind resistance and isn't
all that much worse. It also looks a bit less obtrusive.

Was there one that looked like an oversized FM dipole, that was attached
to the brick walls of houses; ie. below the roofline?
There are a few of those in my area, and they all look suitably ancient.

williamwright

2021-05-29 10:16:18 UTC

Post by Brian Gaff (Sofa)
There were straight dipoles yes, Often used line of sight in the direction
they were looking at, They could and did often have reflection and ghosting
and car interference issues though.

Best not to use one on the front of a house that was next to a main
road. Especially if it was a tram or trackless route.

Bill

Scott

2021-05-29 10:52:06 UTC

On Sat, 29 May 2021 11:16:18 +0100, williamwright

Best not to use one on the front of a house that was next to a main
road. Especially if it was a tram or trackless route.

Sorry about the naive question but was VHF more prone to electrical
interference than UHF or has suppression improved over the years.

Mark Carver

2021-05-29 13:24:59 UTC

Post by Scott
Sorry about the naive question but was VHF more prone to electrical
interference than UHF or has suppression improved over the years.

Both statements are true.

UHF was less prone than VHF, and the top of UHF Band V (Ch 50s/60s) was
less prone than UHF Band IV (Chs 20/30s)

cmwb

2021-05-30 07:24:27 UTC

Post by Mark Carver

Post by Scott
Sorry about the naive question but was VHF more prone to electrical
interference than UHF or has suppression improved over the years.

Both statements are true.
UHF was less prone than VHF, and the top of UHF Band V (Ch 50s/60s) was
less prone than UHF Band IV (Chs 20/30s)

Also moving to negative modulation on UHF meant the interference was less
noticeable,
black noise spots instead of white ones.

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J. P. Gilliver (John)

2021-05-30 09:46:12 UTC

Post by Mark Carver

Post by Scott
Sorry about the naive question but was VHF more prone to electrical
interference than UHF or has suppression improved over the years.

Both statements are true.
UHF was less prone than VHF, and the top of UHF Band V (Ch 50s/60s)
was less prone than UHF Band IV (Chs 20/30s)

Also moving to negative modulation on UHF meant the interference was
less noticeable,
black noise spots instead of white ones.

Though ringing somewhere still gave you white ones too - plus of course
more likely to upset the sync., though as I think by then that was more
likely to be PLL/flywheel than in VHF days, less so.

--
J. P. Gilliver. UMRA: 1960/<1985 MB++G()AL-IS-Ch++(p)***@T+H+Sh0!:`)DNAf

The motto of the Royal Society is: 'Take nobody's word for it'. Scepticism has
value. - Brian Cox, RT 2015/3/14-20

Mark Carver

2021-05-30 10:16:19 UTC

Post by J. P. Gilliver (John)

Post by Mark Carver

Post by Scott
Sorry about the naive question but was VHF more prone to electrical
interference than UHF or has suppression improved over the years.

Both statements are true.
UHF was less prone than VHF, and the top of UHF Band V (Ch 50s/60s)
was less prone than UHF Band IV (Chs 20/30s)

Also moving to negative modulation on UHF meant the interference was
less noticeable,
black noise spots instead of white ones.

Though ringing somewhere still gave you white ones too -

Yes, I don't think there was much in it, after you consider
overshoot/ringing ?

williamwright

2021-05-30 14:32:20 UTC

Post by cmwb
Also moving to negative modulation on UHF meant the interference was
less noticeable,
black noise spots instead of white ones.

Let's not go through all that again.

Bill

williamwright

2021-05-30 14:25:06 UTC

Post by Scott
On Sat, 29 May 2021 11:16:18 +0100, williamwright

Best not to use one on the front of a house that was next to a main
road. Especially if it was a tram or trackless route.

Sorry about the naive question but was VHF more prone to electrical
interference than UHF or has suppression improved over the years.

Much more prone.

Bill

bilou

2021-05-30 18:31:35 UTC

Post by williamwright
Much more prone.
Bill

I think the big improvement is mainly due to the increased directivity.

williamwright

2021-05-30 22:04:59 UTC

Post by bilou

Post by williamwright
Much more prone.
Bill

I think the big improvement is mainly due to the increased directivity.

It was certainly a factor because the e plane directivity of a one-or
two element BI aerial was extremely poor, so with VP there was no real
discrimination against vehicles on the ground below the signal path.

Bill

williamwright

2021-05-29 00:31:23 UTC

Post by Tweed
Thanks Bill. I’m sure I still don’t fully understand how one active arm and
the other 3 elements connected to the braid, with the active arm at 45
degrees to the vertical, makes a better aerial.

The starting point for a theoretical comparison would be understand
fully how a yagi works, then understand fully how competing designs work.

There is a multiplicity of aerial designs that don't rely on the yagi
principle. I think that in many cases they have been reached
empirically, and no-one has ever really investigated them theoretically.
This is especially true for frequencies below about 80MHz, meaning Band
I and the shortwave and AM broadcast bands.

The fact is that the Antiference Antex design really did work well. Me
and my dad were installing them and single dipoles and H aerials for
years and as far as we were concerned the Antex was by far the best, in
fact it wasn't long before we started to use nothing else.

We never used the 'pseudo-antex' aerials that were actually a distorted H.

Antiference guarded their Antex patent jealously because it was a real
money spinner for them.

I have no idea how well the Antex matched 75 ohm feeder and only vague
theories about how it acquired its directional characteristics. I don't
know why the elements had to be 10% longer than those of a centre-fed
dipole to achieve resonance. I can tell you though that the element
lengths were critical, which to me suggests a good, properly tuned and
matched design. The elements were fixed to the central insulator in a
way which made it impossible to mix them up unless you drilled extra
holes, and if you did manage to fit one that was wrong the aerial
wouldn't work at all.

Bill

Brian Gaff (Sofa)

2021-05-29 08:42:05 UTC

Well I also wondered where the sense in those springs in the element clamps
was, The ones I saw had good die cast element clamps so compressing a spring
seemed a bit pointless. My version might have been a knock off then as you
could literarily do what you liked with the jumpers in the insulator and it
came with a metal passivated piece h joined to a tube where the cable came
out of. Quite an art threading it all together it was.

It sounds a bit like aground plane slightly tilted if you only used one
active element.

If they were different lengths then certainly the ones I used were not.

Mystery indeed.
Brian
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Note this Signature is meaningless.!

Thanks Bill. I'm sure I still don't fully understand how one active arm
and
the other 3 elements connected to the braid, with the active arm at 45
degrees to the vertical, makes a better aerial.

The starting point for a theoretical comparison would be understand fully
how a yagi works, then understand fully how competing designs work.
There is a multiplicity of aerial designs that don't rely on the yagi
principle. I think that in many cases they have been reached empirically,
and no-one has ever really investigated them theoretically. This is
especially true for frequencies below about 80MHz, meaning Band I and the
shortwave and AM broadcast bands.
The fact is that the Antiference Antex design really did work well. Me and
my dad were installing them and single dipoles and H aerials for years and
as far as we were concerned the Antex was by far the best, in fact it
wasn't long before we started to use nothing else.
We never used the 'pseudo-antex' aerials that were actually a distorted H.
Antiference guarded their Antex patent jealously because it was a real
money spinner for them.
I have no idea how well the Antex matched 75 ohm feeder and only vague
theories about how it acquired its directional characteristics. I don't
know why the elements had to be 10% longer than those of a centre-fed
dipole to achieve resonance. I can tell you though that the element
lengths were critical, which to me suggests a good, properly tuned and
matched design. The elements were fixed to the central insulator in a way
which made it impossible to mix them up unless you drilled extra holes,
and if you did manage to fit one that was wrong the aerial wouldn't work
at all.
Bill

williamwright

2021-05-29 10:21:40 UTC

Post by Brian Gaff (Sofa)
Well I also wondered where the sense in those springs in the element clamps
was, The ones I saw had good die cast element clamps so compressing a spring
seemed a bit pointless.

The thumbscrew-style nuts had a recess to accommodate the spring. The
purpose of the spring was to retain the nut in transit, because the
aerials were supplied with the elements attached but only loosely so
they could be folded flat and the whole fitted into a thing box. Another
feature of the way the elements were attached was to position the bolts
so all four elements could fold flat.

My version might have been a knock off then as you

Post by Brian Gaff (Sofa)
could literarily do what you liked with the jumpers in the insulator and it
came with a metal passivated piece h joined to a tube where the cable came
out of. Quite an art threading it all together it was.
It sounds a bit like aground plane slightly tilted if you only used one
active element.
If they were different lengths then certainly the ones I used were not.
Mystery indeed.

No mystery Brian. You were not using new boxed items. Everything you say
suggests that you were using items that had been mucked about with.

Bill

Post by Brian Gaff (Sofa)
Brian

tony sayer

2021-05-30 18:49:34 UTC

The starting point for a theoretical comparison would be understand
fully how a yagi works, then understand fully how competing designs work.
There is a multiplicity of aerial designs that don't rely on the yagi
principle. I think that in many cases they have been reached
empirically, and no-one has ever really investigated them theoretically.
This is especially true for frequencies below about 80MHz, meaning Band
I and the shortwave and AM broadcast bands.
The fact is that the Antiference Antex design really did work well. Me
and my dad were installing them and single dipoles and H aerials for
years and as far as we were concerned the Antex was by far the best, in
fact it wasn't long before we started to use nothing else.
We never used the 'pseudo-antex' aerials that were actually a distorted H.
Antiference guarded their Antex patent jealously because it was a real
money spinner for them.
I have no idea how well the Antex matched 75 ohm feeder and only vague
theories about how it acquired its directional characteristics. I don't
know why the elements had to be 10% longer than those of a centre-fed
dipole to achieve resonance. I can tell you though that the element
lengths were critical, which to me suggests a good, properly tuned and
matched design. The elements were fixed to the central insulator in a
way which made it impossible to mix them up unless you drilled extra
holes, and if you did manage to fit one that was wrong the aerial
wouldn't work at all.
Bill

I think that now you don't have as many erections as you once did Bill
then you might like to have a go with NEC modelling!!

https://www.eznec.com/

Takes a bit of learning but if anyone's interested in aerials then its
great for that. I use WINNEC pro, rather clunky, and WINNEC95VM which i
don't think is around but its very easy to use.

You can do some things like look what a single dipole can do where
spaced at given distances from a mast and where it is mounted on said
mast how that can alter the radiation pattern. Let alone add on a
reflector and see how that behaves dependent on spacings and length
etc..

You sort of need to think and visualise things in a three dimensional
axis...

Have fun if you do:)..

--
Tony Sayer

Man is least himself when he talks in his own person.

Give him a keyboard, and he will reveal himself.

cmwb

2021-05-31 07:06:32 UTC

Post by tony sayer
I think that now you don't have as many erections as you once did Bill
then you might like to have a go with NEC modelling!!
https://www.eznec.com/
Takes a bit of learning but if anyone's interested in aerials then its
great for that. I use WINNEC pro, rather clunky, and WINNEC95VM which i
don't think is around but its very easy to use.
You can do some things like look what a single dipole can do where
spaced at given distances from a mast and where it is mounted on said
mast how that can alter the radiation pattern. Let alone add on a
reflector and see how that behaves dependent on spacings and length
etc..
You sort of need to think and visualise things in a three dimensional
axis...
Have fun if you do:)..
--
Tony Sayer

L B Cebik modelled the X aerial 'Antex' so you can also see the results
without the pain of learning :)
http://on5au.be/content/a10/vhf/6mrp.html

Colin

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williamwright

2021-05-31 08:09:28 UTC

Post by cmwb
L B Cebik modelled the X aerial 'Antex' so you can also see the results
without the pain of learning :)
http://on5au.be/content/a10/vhf/6mrp.html

That's extremely interesting, thank you.

Bill

Tweed

2021-05-31 11:58:47 UTC

L B Cebik modelled the X aerial 'Antex' so you can also see the results
without the pain of learning :)
http://on5au.be/content/a10/vhf/6mrp.html
Colin

I’ve just had a read of that (thanks) but unless I’ve read it incorrectly,
he hasn’t modelled the configuration that Bill states, ie 3 legs to the
braid and only one to the coax inner.

I’m also wondering how the design was conceived of in the first place. It
doesn’t seem to be a development of any other antenna design that I’m aware
of.

williamwright

2021-05-31 12:46:56 UTC

Post by Tweed
I’m also wondering how the design was conceived of in the first place. It
doesn’t seem to be a development of any other antenna design that I’m aware
of.

Just random messing about I expect. I wonder if...

Bill

cmwb

2021-06-01 06:32:36 UTC

Post by cmwb
L B Cebik modelled the X aerial 'Antex' so you can also see the results
without the pain of learning :)
http://on5au.be/content/a10/vhf/6mrp.html
Colin

I’ve just had a read of that (thanks) but unless I’ve read it incorrectly,
he hasn’t modelled the configuration that Bill states, ie 3 legs to the
braid and only one to the coax inner.
I’m also wondering how the design was conceived of in the first place. It
doesn’t seem to be a development of any other antenna design that I’m aware
of.

I believe the feed point link (antenna drive point) is between the single
element
and the other three elements joined together in option B and C.
Cebik actually states that the antenna manufacturer (Antiference) used
option B,
since option C provides too much rear lobe performance.

"The ingenuity of the Antiference designers in developing the alternative
feed
system that we have labeled option B provides further flexibility to the
array
and to the potential user."

The benefits are wide forward lobe (easy installation setup) and wide (flat)
bandwidth across the channel.

Colin

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Tweed

2021-06-01 09:02:41 UTC

Post by cmwb
L B Cebik modelled the X aerial 'Antex' so you can also see the results
without the pain of learning :)
http://on5au.be/content/a10/vhf/6mrp.html
Colin

I’ve just had a read of that (thanks) but unless I’ve read it incorrectly,
he hasn’t modelled the configuration that Bill states, ie 3 legs to the
braid and only one to the coax inner.
I’m also wondering how the design was conceived of in the first place. It
doesn’t seem to be a development of any other antenna design that I’m aware
of.

I believe the feed point link (antenna drive point) is between the single
element
and the other three elements joined together in option B and C.
Cebik actually states that the antenna manufacturer (Antiference) used
option B,
since option C provides too much rear lobe performance.
"The ingenuity of the Antiference designers in developing the alternative
feed
system that we have labeled option B provides further flexibility to the
array
and to the potential user."
The benefits are wide forward lobe (easy installation setup) and wide (flat)
bandwidth across the channel.
Colin

Yes, thanks. On re-reading option B seems to be the Antex X. I’d still love
to. Know how this was dreamt up, especially before the days of antenna
modelling software.

Liz Tuddenham

2021-06-01 10:09:18 UTC

Tweed <***@gmail.com> wrote:

[...]

Post by Tweed
I’d still love
to. Know how this was dreamt up, especially before the days of antenna
modelling software.

There was a lot of research done in the 1920s in Bell Labs into the
characteristics of a 'V' aerial (at L.F. and H.F.), which eventually
led to the development of the Rhombic. It would only require a moderate
leap of imagination to wonder if the boom of a V.H.F. Yagi-Uda could be
shortened to zero length by making the reflector 'V'-shaped too.

--
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(Remove the ".invalid"s and add ".co.uk" to reply)
www.poppyrecords.co.uk

tony sayer

2021-06-01 22:32:47 UTC

In article <s94t3h$hcv$***@dont-email.me>, Tweed <***@gmail.com>
scribeth thus

Post by cmwb
L B Cebik modelled the X aerial 'Antex' so you can also see the results
without the pain of learning :)
http://on5au.be/content/a10/vhf/6mrp.html
Colin

I’ve just had a read of that (thanks) but unless I’ve read it incorrectly,
he hasn’t modelled the configuration that Bill states, ie 3 legs to the
braid and only one to the coax inner.
I’m also wondering how the design was conceived of in the first place. It
doesn’t seem to be a development of any other antenna design that I’m aware
of.

I believe the feed point link (antenna drive point) is between the single
element
and the other three elements joined together in option B and C.
Cebik actually states that the antenna manufacturer (Antiference) used
option B,
since option C provides too much rear lobe performance.
"The ingenuity of the Antiference designers in developing the alternative
feed
system that we have labeled option B provides further flexibility to the
array
and to the potential user."
The benefits are wide forward lobe (easy installation setup) and wide (flat)
bandwidth across the channel.
Colin

Yes, thanks. On re-reading option B seems to be the Antex X. I’d still love
to. Know how this was dreamt up, especially before the days of antenna
modelling software.

Probably after a few pints on a handy envelope;?...

--
Tony Sayer

Man is least himself when he talks in his own person.

Give him a keyboard, and he will reveal himself.

tony sayer

2021-06-01 22:31:26 UTC

L B Cebik modelled the X aerial 'Antex' so you can also see the results
without the pain of learning :)
http://on5au.be/content/a10/vhf/6mrp.html
Colin

Yes he did a lot of work like that till he passed away a few years ago
now...

--
Tony Sayer

Man is least himself when he talks in his own person.

Give him a keyboard, and he will reveal himself.

Brian Gaff (Sofa)

2021-05-29 08:24:02 UTC

Like I said, on the ones I've examined there are two arms connected to each
part.
However propagation at those frequencies can be rather odd and its often
try this or that until it works.

Down in my late Grnnies house, every attempt at getting a real band 1 aerial
to work without ghosting failed, but weirdly, a piece of very stiff wire
along the top of the curtain rail and dangling down a couple of feet the
other end worked perfectly unless somebody stood in the front rear of the
sitting room.

Brian
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The Sofa of Brian Gaff...
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Blind user, so no pictures please
Note this Signature is meaningless.!

Post by Tweed
Just peering up at the roof tops in Bewdley just now I spotted a band 1 X,
band 3 multi element combination in excellent condition. This led me to
realise that I can't explain why the band 1 aerial is an X. Can anyone
explain its advantages over a vertical dipole, or the H antenna (which is
presumably a dipole and director).

Thanks Bill. I'm sure I still don't fully understand how one active arm
and
the other 3 elements connected to the braid, with the active arm at 45
degrees to the vertical, makes a better aerial.

Scott

2021-05-29 08:39:55 UTC

On Sat, 29 May 2021 09:24:02 +0100, "Brian Gaff $Sofa$"

Post by Brian Gaff (Sofa)
Like I said, on the ones I've examined there are two arms connected to each
part.
However propagation at those frequencies can be rather odd and its often
try this or that until it works.
Down in my late Grnnies house, every attempt at getting a real band 1 aerial
to work without ghosting failed, but weirdly, a piece of very stiff wire
along the top of the curtain rail and dangling down a couple of feet the
other end worked perfectly unless somebody stood in the front rear of the
sitting room.

Could the signal have been too strong? Would an attenuator have
helped?

Brian Gaff (Sofa)

2021-05-29 08:18:11 UTC

The Antex could be wired as vertical or horizontal simply by moving two
links inside the insulator. It is as far as I can see just a dipole. The two
rods being one leg of it. Many people just cut the legs to size and stuffed
a rubber bung in the end. However they were pretty broad band even as they
came. I assumed that it was analogous to the old bats ears uhf type, but
with the solid bit represented by two rods instead of a flat bit which
widened as it got further from the insulator.
My guess is that it probably matched better by doing that.

In them old days of yore of dx TV on band 1, one could modify one with two
holes underneath and put a short phasing harness in and a matching stub of
50ohm coax and put the whole thing horizontally so it could get good
Sporadic E reception. These signals notoriously had phase issues and the 45
degree harness did to some extent even this out a bit as signals were mostly
coming from above.

The combined aerials, I never found to be all that good myself, as they
diplexer the signals and certainly were nowhere near as broad band on band
3 as the X was on band 1.
You could do wonders with home made single channel five element yagis on
band three though, from my location. Strangely, vertically polarised
stations always seemed more prone to interference and flutter from aircraft,
I guess that is the different polar response when mounted vertically.
Brian
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williamwright

2021-05-29 10:14:19 UTC

Post by Brian Gaff (Sofa)
The Antex could be wired as vertical or horizontal simply by moving two
links inside the insulator.

Antiference used cable saddles (short strips of aluminium with holes at
each end and a quarter-circle 'dint' in the middle) for the links
between the elements, but that didn't mean that you were supposed to
alter therm around. The way to use an Antex for HP was to mount it
horizontally.

It is as far as I can see just a dipole. The two

Post by Brian Gaff (Sofa)
rods being one leg of it. Many people just cut the legs to size and stuffed
a rubber bung in the end. However they were pretty broad band even as they
came.

They were available for individual channels, which suggests that they
weren't very wideband.

Bill

Brian Gaff (Sofa)

2021-05-30 07:58:21 UTC

Well all the ones around here, and nothing to do with me, were mounted
vertically and since I inherited one to turn into a sporadic E aerial which
was mounted horizontally I could see that it was in fact strapped with those
strips you mention and as a Dipole with two rods on each leg when I got it.
I modified it so it was crossed dipoles with a phasing harness between them.

I had to drill some holes in the side for this piece of coax, but the side
became the bottom of course.
Brian
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Post by Brian Gaff (Sofa)
The Antex could be wired as vertical or horizontal simply by moving two
links inside the insulator.

Antiference used cable saddles (short strips of aluminium with holes at
each end and a quarter-circle 'dint' in the middle) for the links between
the elements, but that didn't mean that you were supposed to alter therm
around. The way to use an Antex for HP was to mount it horizontally.
It is as far as I can see just a dipole. The two

Post by Brian Gaff (Sofa)
rods being one leg of it. Many people just cut the legs to size and stuffed
a rubber bung in the end. However they were pretty broad band even as they
came.

They were available for individual channels, which suggests that they
weren't very wideband.
Bill

williamwright

2021-05-30 14:33:28 UTC