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13th Jan 2018

i made this mostly to answer a question from NoVIcE about the spherical vs parabolic shape of antenna reflectors. this type of antenna uses a spherical reflector and you probably have one outside your house if you get sattelite tv.

radical dish antenna communication radio science

Comments

mccafferty2 15th Jan 2018

This is why i love tpt
NoVIcE 15th Jan 2018

Hey, why do i see spherical offset antennas so often, are they cheaper than parabolic ones? It seems strange because for a parabolic one, it looks like you will need less precision to place the transmitter/reciever. Thats my guess IMO. So, why arent parabolic more abundant?
Security-Drone 15th Jan 2018

"rrrrrefraction is dhe biinding of a rrray ohf lyght" as my dad's old science prof used to say. (Transliteration: Refraction is the bending of a ray of light.- He had dodgy pronunciation) But I see what your getting at. :P
sentinal-5 14th Jan 2018

in 2d like TPT you'd be absolutely right, but prisms only allow for a 1d transformation, whereas with a 3d dish reflector you can capture a 2d plane of signal and compress it all into a point focus with just one transformation. there are certain types of antenna that use lenses, but obviously that isn't as simple in RF as it is in visible light. RF lenses actually end up being a series of concentric spheres of extremely specific dimentions.
SpamBot-01 14th Jan 2018

Frankly I think prisms would be a better way to go but I see what your getting at. :P
sentinal-5 14th Jan 2018

there are a lot of really fascinating things about rf hardware i'd love to post. unfourtunately i'm really ill at the moment so they're going to have to wait. oh and then there's the fact that i'm not even sure i can build a working gregorian offset reflector in TPT lol.
TheNik 13th Jan 2018

This is pretty awesome, I never knew that was a thing. Thank you!
NoVIcE 13th Jan 2018

Oh yeah, so thats how these work. This is very interesting exploiting of geometry.
Jacek_hax 13th Jan 2018

umm how does this work
sentinal-5 13th Jan 2018

thanks :D

The Powder Toy

Spherical offset antenna by sentinal-5

Comments