sheet metal

[brotherhood]

hi guys
if i put sheet metal on my friends BUD ,would i get a stronger signal for c and ku also
expressvu?
thankyou

 

[voomvoom]

Good Question! I'd say probably not, you would need to get the curvature of the sheet metal to reflect the signal to it's proper focal point. It might work and it might not work? I've seen pictures of hand made dishes from the middle east (I think), where the people beat cans into a parabolic shape and were able to receive signals. But, you're talking about improving on signal. Well, it might work and it might not work. If you could get the curvature correct it would probably work, but at the same time, it might not improve the signal? Give it a try, and let us know the results.

Al

 

[voomvoom]

Another thing to maybe think about, you wouldn't want to reflect direct sun light into the focal point either. It might cause the noise factor (Kevin) to get awful hot? So, if you try this, you may want to paint the sheet metal?

Al

 

[Diamond Jim]

Brotherhood,

What kind of dish are you talking about, mesh or solid?

I have heard about putting sheet metal over a mesh dish because the holes were too big to catch Ku signals. Al, have you ever heard of doing this?

I personally don't see where it would do any good on a solid dish unless it was to cover a damaged area. But, what do I know?

 

[brotherhood]

sorry
yes 12foot mesh dish

 

[TiminMb]

For Ku, it would depend on the size of the holes in the mesh. For C band, being a lower frequency and longer wavelength, there would be no improvement as the radio waves at C band wavelength already see it as a solid object.

 

[mikekohl]

Usually a bad idea, from the reasons already given.
I experimented with replacement solid aluminum sheeting
in an 8-1/2 foot Orbitron antenna, in the Middle East
over 15 years ago.

The Saudi Arabian sun is unforgiving to anything near the focal point,
so unless you can rough up the material so that it does not shine,
or paint it a pastel color, the solar radiation will tend to destroy
or otherwise melt feedhorns, etc.

We did our work at night, and found that the solid panels were much
less able to be formed into a perfect parabolic in the same manner as
mesh material, so Ku-band performance suffered.

If you want good Ku-band, use a large offset antenna such as those in
the 1.8 or 2.4 meter size, and appropriate LNBF. Same with DBS in out-of-
CONUS locations. Yuo