TV Dish Lnb project!!

[epilot]

hi there

i wanna see if there is any circuit for an lnb and TV receivers?

even a simple circuit for 1 chanel is very good :lol:

thanks for any help

 

[JohnBrown]

At LNB frequencies it's not so much a circuit as a plumbing exercise. I doubt that you would be able to build one.

 

[epilot]

thanks for the answer
but i am in doubt if there is no ANY circuit for teach???
even an analog LNB circuit !? :cry:

 

[Nigel Goodwin]

thanks for the answer
but i am in doubt if there is no ANY circuit for teach???
even an analog LNB circuit !? :cry:

ALL LNB's are analog!, it makes no difference whatsoever if the signals they receive are analog or digital, the only difference is that the so called 'digital' ones were high band and low band, switched by a 22KHz tone.

I've never seen a circuit for one, as suggested it's NOT something you could really build at home!.

But it's basically a simple device, just a down converter, you need:

A tuned filter, wide enough for the section of band you want to receive.
A mixer.
A local oscillator, these are usually simple LC designs, so not too stable!.
A tuned output filter, again wide enough for the frequencies in use.

You also need to design for it to be powered via the output cable, and to switch polarities depending on the incoming supply voltage. If you want dual band, you need to arrange 22KHz switching as well, and to alter the frequency of the local oscillator accordingly.

 

[epilot]

Oh so it seems it is hard to build one
i think it is better i go for other thing and other device :roll:

anyway thanks for all helps specially your helps Nigel