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What to do with a satellite dish

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LAN_403

Pinky's Brain

Tue Aug 21 2012, 04:00PM

Registered Member #2901 Joined: Thu Jun 03 2010, 01:25PM
Location:
Posts: 837

BigBad wrote ...

1N82 or another type of diode works apparently.

Did you happen to see how many diodes that took ... also I don't think you can buy cat whisker germanium diodes any more, so what are you going to use which can efficiently rectify a couple GHz AC voltage?

I didn't really consider something which would take 100s or more dollars worth of microwave diodes realistic.

Steve Conner

Tue Aug 21 2012, 04:11PM

Registered Member #30 Joined: Fri Feb 03 2006, 10:52AM
Location: Glasgow, Scotland
Posts: 6706

Well, the reason you can't buy 1N82s any more is because Schottky "hot-carrier" signal diodes like the 1N5711, HP 5082-2800 or MBD301 outperform them.

I've made a ghetto "wireless power receiver" using one of these diodes soldered in inverse parallel across an LED, and the leads trimmed to be a half-wave dipole at 2.4GHz. I'm sure it would have worked a lot better with two Schottky diodes in a proper rectifier arrangement.

Conundrum

Wed Aug 22 2012, 09:37PM

Registered Member #96 Joined: Thu Feb 09 2006, 05:37PM
Location: CI, Earth
Posts: 4061

Interesting.
Am I right in saying that the reason LEDs won't work directly is the junction capacitance?

If so then applying a small reverse DC bias to offset the capacitance should allow it to rectify the MW signals.

edit:- And the Vfwd, however a standard cheap 1N4148 with a DC bias in reverse derived from the rectified power should be enough to bootstrap it into life.

-A

Pinky's Brain

Wed Aug 22 2012, 09:44PM

Registered Member #2901 Joined: Thu Jun 03 2010, 01:25PM
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They will both just short at a couple GHz because of reverse recovery.

Yanom

Wed Aug 22 2012, 10:49PM

Registered Member #4659 Joined: Sun Apr 29 2012, 06:14PM
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Posts: 158

here's one that hasn't been mentioned yet - use it like the parabolic antenna that it is. Put some sort of wi-fi recieving device in the focal point of the dish, point it at a distant hotspot, and bam! crystal clear signal.

genious 7

Thu Aug 23 2012, 02:11PM

Registered Member #2887 Joined: Sat May 29 2010, 11:10PM
Location: Panama City, Panama
Posts: 107

Err..., I did, I suggested to "borrow" wifi from a neighbor half a mile away. Just put a usb wifi dongle in the focal point, aim and profit.

Conundrum

Sat Aug 25 2012, 06:40AM

Registered Member #96 Joined: Thu Feb 09 2006, 05:37PM
Location: CI, Earth
Posts: 4061

I have a very large dish here, might try that.

It also could be worth silvering it, making a waterproof casing and mounting the dish horizontally so it can be used for both solar power and wifi/BT/SETI with a wire a la Arecibo.

radiotech

Sat Aug 25 2012, 05:53PM

Registered Member #2463 Joined: Wed Nov 11 2009, 03:49AM
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Posts: 1546

Apart from the dish, the support arm structures are good for positioning things on the wall
or roof and adjusting them to whatever angle you want.

Nik

Mon Aug 27 2012, 04:22AM

Registered Member #53 Joined: Thu Feb 09 2006, 04:31AM
Location: Ontario, Canada
Posts: 638

exploding wire at the focal point, deafen yourself from 100m

Some how this idea tickled the todo list part of my brain more then any of the others.

The solar cooker/sterling power are both interesting ideas but tracking the sun might be an issue. Also having a spare dish on the house I might have to try it out.

Tetris

Tue Aug 28 2012, 01:58AM

Registered Member #4016 Joined: Thu Jul 21 2011, 01:52AM
Location: Gainesville, FL
Posts: 660

1. Cover it in foil and fry an egg on it.
2. Build a frequency jammer for cell phones, keep it in your car, and drive near a high school at let out time. Look inside the cars for frustrated teens.
3. Parasol-like thing
4. Stick it in a random ghetto, and watch as people attempt to "hack in" to a non-existent service.
5. This was from my electronics teacher:
1. Get satellite service. Tune out your room mate's/ parent's/ spouse's favorite channel so that only whenever they touch it, the signal comes.
2. Build a jammer, and say that only when they touch it, the signal comes, and then this is a lot easier to piss them off.
6. Spray paint a lion's mane on it, and pretend to be Simba
7. Put it on top of a pile of electronics in a wagon, and walk into town with it.
8. Crank up the radio energy all the way, and fry an egg by the radiation itself.
9. Give it to a cat. Cats will always find something do do with everything.
10. Use it as an epic towel rack.
11. Put it on your front door to weird people out.
12. Give it to a clueless person and tell them that it possesses magical powers if they can get it to work.
13. Ice cream bowl.
14. Curry bowl.
15. Stuff it under your shirt backwards and pretend you're a pregnant woman.
16. Stuff it under your shirt frontwards, with part of it under your pants.
17. Put it on a Tesla Coil.
18. Connect it to something and see what station you can make it receive by touching it.
19. Spend an hour with your face on it while it is on and see if you feel funny later.
20. Decorative ornament.
21. Use as sink bowl?
22. Spend a while with it on your roof, and pretend to be fixing it up.
23. Actually install it yourself.
24. How high of a voltage can it take before going POOF?
25. This is 4HV, make it HV related: EMP it.
26. Get another one and put them together. Make a giant portrait of a woman this way with old electronics parts.
27. Pretend to be a ghost buster, and take it around town pointing it at everybody.

And that's all I can think of...

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