A length of cable from the splitter but with nothing on the far end ( an unterminated stub ) can degrade the signal to other TV.s Signals arriving at an unterminated cable end are reflected back like an echo to the splitter. The TV receivers have the incoming signal ( that they need ) mixed with an echo which can degrade signal and possibly picture quality.

Putting a 75 Ohm resistive terminator at the end of a stub can result in an improved signal quality.
All very true of course but any decent splitter has about 25dB loss output to output so the echo is largely attenuated.
 
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Altered the 28 element aerial by sitting it on a cardboard box so that the prongs are vertical, retuned. I have 97 signal strength & 100 picture quality.

That seems to have cracked it.

Thank you.
There are no 28 element aerials, the max is generally 21. Someone is lying and counted the elements (not prongs) twice or often 4 times.
 
Presumably my aerial was intended for analogue? And needs scrapping.

There is no such thing as a digital antenna, they are all analogue - the difference is that the signal they pick up is digital. Not withstanding - a different antenna may be needed since the switch to digital transmission began, because they may be transmitted on different frequencies, requiring a different antenna bands or groups.
 
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There are no 28 element aerials, the max is generally 21. Someone is lying and counted the elements (not prongs) twice or often 4 times.
Typical mistake by winston1 correcting the person asking for help when the original poster is very likely to be correct. I suggest yet again that winston1 checks before giving incorrect information. A very quick google comes up with:
https://connectec.uk/av-tv-and-sate...PHu-TdUdI8AzOEIFtFwfnTfCGf9qtwQhoCSi8QAvD_BwE
Which is a genuine 28 element TV aerial.


Also in the google search I found a 48 element:https://www.toolstation.com/digital-tv-aerial/p54040

Personally I would refer to it as 11 element but if the TV aerial industry as a whole is happy to call it 48 then there is zero point in trying to confuse those from outside the industry by saying the manufacturers are wrong.

Behind my shed I have an old aerial from the chimney which was pointing at Crystal Palace:
upload_2021-9-29_19-10-56.png

This is about 3m or more long but the camera flash couldn't cope with all of it, this shows less than half of 29 directors and reflecter (total of 6 elements) & dipole and which I make 31 elements but manufacturers may call 36 elements.
 
Typical of SUNRAY to accuse me of being wrong when I am not. Your first link shows a 14 element log periodic aerial wrongly described as a 28 element because someone has counted the elements twice. Your second link shows, as you say, an 11 element. I cannot see how any one would come up with 48 even counting the directors 4 times and the reflector 6 times.
The TV aerial industry as a whole do not count the elements several times, it is only some of the less reputable manufacturers, and electrical suppliers who know nothing about aerials that do this.
I cannot comment on the aerial behind your shed as the picture is not good enough.
 
Typical of SUNRAY to accuse me of being wrong when I am not. Your first link shows a 14 element log periodic aerial wrongly described as a 28 element because someone has counted the elements twice. Your second link shows, as you say, an 11 element. I cannot see how any one would come up with 48 even counting the directors 4 times and the reflector 6 times.
The TV aerial industry as a whole do not count the elements several times, it is only some of the less reputable manufacturers, and electrical suppliers who know nothing about aerials that do this.
I cannot comment on the aerial behind your shed as the picture is not good enough.
No. the log periodic aerial linked to has 28 independant elements. I'm not going to insult you by describing how a log periodic is constructed. opposing halves of what behaves like a dipole are not one element, they are 2 elements, always have been described as 2 elements by the designer and I see no reason to redefine it.
Regardless of your opinion, if a manufacturer describes it as 48 elements then that is what one would have to order when purchasing. A member of the public wanting an aerial will not have a reason to order it as anything different to the manufacturers description.
Over the years I've purchased many radio mic TV aerials from Alltrade (which incidently I usually cut down to about 4 elements; reflector, dipole & 2 directors) and, by inference, you describe them and the likes of Labgear & Antiference (and for that matter some Italian products) less reputable. So be it.

As to the aerial behind my shed, I warned the flash didn't penetrate far but you can see about a 40% of the boom and a dozen of the 29 directors. For clarification that is 29 pieces of aluminium ~6" long mounted across the boom, just the way you describe them. On this occasion you would call it 31 elements.
 
No. the log periodic aerial linked to has 28 independant elements. Opposing halves of what behaves like a dipole are not one element, they are 2 elements, always have been described as 2 elements by the designer and I see no reason to redefine it.
I disagree.
Regardless of your opinion, if a manufacturer describes it as 48 elements then that is what one would have to order when purchasing. A member of the public wanting an aerial will not have a reason to order it as anything different to the manufacturers description.
The manufacturer needs educating. Or better still needs to be avoided in favour of one who knows what he is selling. Dipoles have always been one element not 2 or 4. Likewise a reflector has always been regarded as one element whether it is a single sheet of ali or several rods. These large numbers are used because the public thinks more is better.
As to the aerial behind my shed, I warned the flash didn't penetrate far but you can see about a 40% of the boom and a dozen of the 29 directors. For clarification that is 29 pieces of aluminium ~6" long mounted across the boom, just the way you describe them. On this occasion you would call it 31 elements.

OK. That is unusually big.
 

The manufacturer needs educating. Or better still needs to be avoided in favour of one who knows what he is selling. Dipoles have always been one element

Yet again Winston1 is wrong


https://www.electronics-notes.com/a...tion/dipole-antenna/dipole-antenna-aerial.php

Dipole antenna basics
The name 'di-pole' indicates that the dipole antenna consists of two poles or items – two conductive elements.

Current flows in these two conductive elements and the current and the associated voltage causes an electromagnetic wave or radio signal to be radiated outwards from the antenna.
 


Yet again Winston1 is wrong


https://www.electronics-notes.com/a...tion/dipole-antenna/dipole-antenna-aerial.php

Dipole antenna basics
The name 'di-pole' indicates that the dipole antenna consists of two poles or items – two conductive elements.

Current flows in these two conductive elements and the current and the associated voltage causes an electromagnetic wave or radio signal to be radiated outwards from the antenna.

Correct - that is what the 'di' part in dipole implies. A monopole is a single element.
 
Just to confuse the matter, a folded dipole,

Is a folded dipole (a) a single element or (b) three elements, two quarter wave elements and one half wave element. ?
 
The manufacturer needs educating. Or better still needs to be avoided in favour of one who knows what he is selling.

Tell me winston1 if you were ordering a new car, for the sake of the discussion a Ford Fiesta 1.3, would you argue the manufacturer is not reputable?
 
Just to confuse the matter, a folded dipole,

Is a folded dipole (a) a single element or (b) three elements, two quarter wave elements and one half wave element. ?

I would venture to suggest it is two elements, despite being a single part, otherwise it would not have the 'di' part in the name.
 

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