Terminology question

RimaNTSS

RimaNTSS

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Hi community! @a33 and me had a chat on some English terminology (Dutchman and Latvian arguing on English terms.... funny). Well, of couyrse we were not arguing but friendly chatting. The question is: How the angle AFB should be called? I always used term "Antenna's opening angle" and it sound logical to me as a direct translation from Latvian and Russian. So, please , how should we call this angle? ScreenHunter_662 May. 28 11.59.jpg
 
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Hi community! @a33 and me had a chat on some English terminology (Dutchman and Latvian arguing on English terms.... funny). Well, of couyrse we were not arguing but friendly chatting. The question is: How the angle AFB should be called? I always used term "Antenna's opening angle" and it sound logical to me as a direct translation from Latvian and Russian. So, please , how should we call this angle? View attachment 117755
My logical answer would be, LNB position angle. But then I have a Dorset logic.
 
RimaNTSS

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In my understanding LNB had "Illumination angle" and best option is to have match of Illumination angle to Opening angle.
 
Channel Hopper

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The angle between A and B when correctly illuminated by the feedhorn is also called 'aperture angle'
 
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Hi community! @a33 and me had a chat on some English terminology (Dutchman and Latvian arguing on English terms.... funny). Well, of couyrse we were not arguing but friendly chatting. The question is: How the angle AFB should be called? I always used term "Antenna's opening angle" and it sound logical to me as a direct translation from Latvian and Russian. So, please , how should we call this angle?
Well, as another non-English, I would chime in for the opening angle.
This makes sense for both dish and feedhorn (although they are different in construction, they have similar purpose).

(Except, if you think about what way the signals travel when receiving, we should probably call it the "closing angle" when used for Rx??)
 
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The angle between A and B when correctly illuminated by the feedhorn is also called 'aperture angle'
...is probably the most correct term.

But in the community it's a bit like referring to VSAT antennas (Very Small Aperture Terminal, AFAIR), when you can just say "sat dish"... :)
 
RimaNTSS

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Actually, Aperture angle was one of the options we discussed (me and @a33) even before starting this thread. But I do not feel that Aperture angle term is so common as Opening angle or Viewing angle.
 
Channel Hopper

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...is probably the most correct term.

But in the community it's a bit like referring to VSAT antennas (Very Small Aperture Terminal, AFAIR), when you can just say "sat dish"... :)
VSATs were origianally associated with single polarity systems and once you see the focal equipment of the narrowband versions, you get to understsand why.

https://www.mwavellc.com/wp-content/uploads/2017/01/RP40X10-93-90F-Shaped-Beam-X-band-Radar-Antenna.pdf

Enthusiasts like those on this forum stretch the parameters to receive stuff that would not be normally within the bands of C, Ku and Ka, and so the VSAT nomenclature cannot easily be associated with some of the genius designs that appear out of the blue, coping with issues in picking up a particular signal.
 
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a33

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Hi all!

Would 'opening angle' and 'aperture angle' mean about the same thing in English?

I would like to use these terms for the angle RimaNSS described above, but I found that at least in Dutch language, the term 'opening angle' (openingshoek) is also used for the width or narrowness of a beam towards the satellites; relevant for the degree of interference from neigbouring satellites.

Copy from wikipedia, lemma "omroepsatelliet", translated to English:
When a satellite dish has the strongest signal, the optical axis of the paraboloid points precisely to the satellite. If the dish does not exactly point to the satellite, the field strength decreases. The total angle of rotation at which the field strength differs by about 3B is called the opening angle. This angle becomes smaller when the dish becomes larger.

So if the term is used for two different things (dish to LNB angle, and dish to satellites angle), that would be confusing.

Or is there also a direct link (1 to 1 relation) with this opening angle towards the satellite, and the dish-LNB illumination angle?

I hope you can shine some light on this.

Greetz,
A33
 
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The only real terminology you need to remember is "Hummer" and "Puppy"...

Hummer is used when plugging it into a power source, "Whats this Hummer do?" used for anything electrical.

And if it does not use power, or does nothing when plugged in then "That Puppy looks dead"...Or a tool, "hand me that Puppy"

Things like that there.........Now where did that puppy go?...Is that Hummer buzzing?
 
RimaNTSS

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The total angle of rotation at which the field strength differs by about 3B is called the opening angle. This angle becomes smaller when the dish becomes larger.
Is not that beamwidth?
 
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a33

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Is not that beamwidth?
Good question. I don't know.
Another incorrect or confusing use of a satellite term?
I think we need a dictionary with definitions, that everybody follows...

BTW I saw the automatic translation in my previous post mentions 3B, of course that should be 3 dB!

greetz,
A33
 
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