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Alternative Uses For an Old Satellite Dish?
ya really writes "My family has one of those BUDs (Big Ugly Dishes) sitting in their back yard still. The other day they asked me if I would take it apart for them. Aside from simply recycling it, I was wondering if there are any alternatives for its use. It was one of the last made before DirectTV and Dish took over satellite broadcasting, and even has a digital receiver. I'd say it was made around 1996."
or cover it with tinfoil to run a sterling engine??
Go over to lyngsat.com and see what you can see. Satellite TV is far more than what the media companies are willing to sell you.
Get a different receiver and you can receive weather satellite data, etc., directly. Hook up with your local ham radio group for more info.
Since little USB wifi and bluetooth adaptors are so cheap, you could mount one of those at the dish focus. Make a wooden block to hold in, which replaces the LNB.
Although the reflectors for either C or Ku band dishes would work fine, it should be noted that the FCC regulates the effective radiated power. Check out FCC EIRP (equivalent isotropic radiated power) Limits.
The reference is an isotropic radiator... like having a point source radiating energy equally in ALL directions (up and down as well as the horizontal plane. A vertically oriented half-wavelength dipole has 2.15 dB gain over an isotropic radiator. If vertical, it radiates equally in all directions horizontally, but drops to nothing straight up and straight down.
Many have used a dipole as an alternate reference since it the lowest gain and most basic antenna normally constructed.
The EIRP rating is basically the amount of power it would take fed into an isotropic antenna to equal the signal produced from the gain (focusing effect) of a directional antenna. Some get confused by antenna gain. It doesn't give us more power than a transmitter puts out, it just concentrates the signal in a desired (hopefully!) direction at the expense of other directions.
The FCC rule differ for point to point versus point to multipoint WiFi. Point to multipoint the limit is 4 Watts effective regardless of antenna gain. (36 dBm, m being mw or milliwatts) A 100 mw card (20dbmw) feeding a 16 dBi gain antenna would produce 36 dbmw EIRP if there was no cable loss. If 3 dB was lost, it would take 200 mw into the cable to compensate (23dbm -3dB + 16dBi = 36
Point to multipoint starts at the level for a low gain antenna, but only requires a fairly small reduction in transmitter output power as higher antenna gain is used. So the maximum allowable signal does increase quite a bit with higher gain antennas.
Since things are pretty close to line of sight at 2.4 GHz, a huge dish near the ground (and not pointing up in the sky) isn't likely to do nearly as well as a smaller one up above the clutter. So most C band dishes (usually 2 to 4 meters across) are too big for most situations. Gain is probably best estimated by comparison with commercial dishes of the same diameter and frequency.
Allowable power is likely different in other countries. Your mileage (kilometerage????) may vary