easy guide to calcullate the focal point of the off-set dish....

georgekamal

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dear friends and experts ,please guide me in following matter, is that 'how to
calcullate the focal point of the off-set dish? and i need step by step easy
guide..........b cause i'm very new and help less for this matter.

thankx for any help- regards-george
 

Channel Hopper

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There isn't one.

Sorry
 

Birdseye

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I've heard many times that this is impossible. But surely if you coat the dish with aluminum silver car paint or coat it in tin foil it will reflect light to a focus point which you can find on a sunny day with a bit of paper and experimentation??? (As its an offset dish I assume you'll have some idea where the LNB should be already.)

As the dish is a reflector it will work the same for both light and radio waves of the size used in Satellite. I've heard stories about shiny transparent dishes burning out LNBs for this very same reason.

Obviously before using it for real, you'll need to un-silver the dish.... or cook your LNB. Good luck!
 
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Jeff_19341

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The same can be achieved by sticking half a dozen of the small mirror tiles to the dish surface, so I have been led to understand.
 

2cvbloke

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Jeff_19341 said:
The same can be achieved by sticking half a dozen of the small mirror tiles to the dish surface, so I have been led to understand.

Have to be careful doing that, I've seen parabolic mirrors setting fire to stuff after reflecting sunlight... :D
 

rolfw

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Yes, I've heard it's a dangerous thing to do, my mate had a real problem. :)
 
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Jeff_19341

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One presumes that the operative has enough sense to remove the small mirror tiles (approx 1 inch square) after they have found the focal point of their dish

PS Rolf, no image on your above post.
 

rolfw

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Whoops, tended to lose the impact. ;)
 

2cvbloke

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Jeff_19341 said:
That's a bit drastic:(

It's just a joke!!! I'm sure anyone with a string of intelligence would use a lightbulb... :D
 
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