Hi Group,

Over the last few years, I have picked up several of the DirectTV disk
which are for 10GHz and most all have a diameter of about 15 to 20
inches.

If I operate a 15 inch disk on 2.4GHz, what gain would I expect?
And, how would this compare to a 20 inch disk?


I am looking forward to your comments!

de KJ4UO

difference ~2.5 dB.

wrote:
Hi Group,

Over the last few years, I have picked up several of the DirectTV disk
which are for 10GHz and most all have a diameter of about 15 to 20
inches.

If I operate a 15 inch disk on 2.4GHz, what gain would I expect?
And, how would this compare to a 20 inch disk?


I am looking forward to your comments!

de KJ4UO

I'm sure you will get a more precise answer from those with experience
at 2.4 GHz or who can model the antenna effectively.

For a quick approximation I use the ratio of the square wavelengths. So,
2.4 GHz ~ 5 inch wavelength. A 15 inch [3 wavelength] diameter will
exhibit an approximate gain of 9 square wavelengths or something around
9 to 10 dB at 2.4 GHz. This will most likely may be off target by up to
2 or 3 dB.

Anyone have a more precise estimate or calculation?

/S/ W1MCE

wrote:

Hi Group,

Over the last few years, I have picked up several of the DirectTV disk
which are for 10GHz and most all have a diameter of about 15 to 20
inches.

If I operate a 15 inch disk on 2.4GHz, what gain would I expect?
And, how would this compare to a 20 inch disk?


I am looking forward to your comments!

de KJ4UO

Hi Group,

Over the last few years, I have picked up several of the DirectTV disk
which are for 10GHz and most all have a diameter of about 15 to 20
inches.

If I operate a 15 inch disk on 2.4GHz, what gain would I expect?
And, how would this compare to a 20 inch disk?


I am looking forward to your comments!

de KJ4UO

I did not run the numbers, but my concern would be properly illuminating
the surface. Fortunately, the dish is offset fed so feed blockage will not
be a concern.. Go to the W1GHZ site to see appropriate high F/D feeds to
illuminate this surface.

Dale W4OP