Students from the Indian Institute of Science Education and Research combined a commercial satellite dish, a satellite finder and an Arduino, and produced a workable radio telescope. The satellite dish provides the LNB (low noise block) and the associated set-top box is used only for power. Their LNB employs an aluminum foil shield to block extraneous signals.
In addition to the hardware, the team built Python software to analyze the data and show several practical applications. They used known geostationary satellites to calibrate the signal from the finder (digitized by the Arduino) to determine power per unit voltage. They also calculated the beam width (about 3.4 degrees) and used the sun for other calibration steps.
Continue reading “Listen to the Sun, Saturn, and the Milky Way with Your Own Radio Telescope”
Satellite dishes are a common site these days, although admittedly most of them are Ku- and Ka-band dishes. The older C-band dishes are still around, though, just less frequently in people’s yards. [Greenish Apple] decide to cut the cable and start watching free TV so he built a C-band dish. The trick is, he made the dish out of wood.
The design is the offset type, not a prime focus dish–that is, the electronics are not in the center of the dish but on the side. Wood isn’t particularly good at reflecting RF, of course, so over the wooden skeleton, he used flashing.
Continue reading “Would You Like a Satellite Dish?”
Love the classic brick Game Boy, but hate the low-contrast LCD, terrible battery life, and the inability to play Pokemon Emerald? This one’s just for you. It’s the ultimate DMG Game Boy – a Game Boy Advance SP stuffed (is it stuffed if it’s taking up more room?) into the classic Game Boy enclosure. Forum thread.
Zooming in to a microchip. It starts off with a DSLR and ends up on a scanning electron microscope. This is an older chip, and the CPU you’re using right now probably has much smaller features.
Every movie and every TV show set in space invariably has space helmets with LEDs pointing towards the face. Think how annoying that would be for an astronaut. Here’s how you add LEDs to a space helmet for a nice theatrical effect. Just don’t use it on a real EVA.
Everyone’s favorite crowdfunded space probe can apparently be detected with an 8-foot dish. That’s the same size as an old C-band dish, a.k.a West Virginia wildflowers. We know some of you have one of these out there, so go make a ~2GHz feed horn, grab a USB TV dongle, write it up, and send it in.
Alright, MAME cabinets. Say you want to go old-school and have a CRT. Some arcade games use a vertically oriented display, while other, slightly more modern games use a horizontally mounted display. How do you fix this? Get a big bearing, of course. This one allows a 19″ CRT to be rotated 90 degrees – all you need, really, if you’re switching between Pacman and Mortal Kombat.
Hey mechanical keyboard enthusiasts! Here’s some Hackaday Cherry MX keycaps. Informal interest check in the comments below. Suggestions welcome.
Hone your survival skills by harnessing the sun’s rays to cook your meals. [Robert] and his daughter turned an old satellite dish into a solar cooker. The image above shows them baking some potatoes, but the temperatures inside the cast iron vessel are high enough to let you cook most foods.
The dish was originally used for satellite television but has been collecting dust in the shed for quite some time. When [Robert] came across a roll of foil tape in his workshop he decided to give the project a whirl. His daughter helped out by peeling away the tape backing (this can be much harder than it sounds) while he applied the reflective material trying to keep it free of wrinkles. After a close call [Robert] donned a pair of welding goggles when positioning the dish. If the light intensity can get the pot up as high as 428 degree Fahrenheit we’re sure it can cause flash blindness.
Unlike other dish cookers we’ve seen, [Robert] didn’t use the original mount for holding the dish in place. He just set it on three bricks and directed it by hand. To keep the intensity focused on the kettle he had to reposition it every 15 minutes.
We wonder if the heat is too much for building a sun tracking solar power harvester?
Grab that old satellite dish out of the dark corner of you garage and get those hot dogs ready. [Share alike license] is going to show us how to turn the dish into a solar cooker.
Harnessing the sun’s power requires a reflective surface. Although the image above makes it look like a mirror finish, this is really just covered in foil tape. This is what’s used to seal duct work and can be had for a few bucks at any home store. You’ll notice the dish is pointed up quite a bit more than it would have been when receiving satellite television. The mount on the back of the dish has been turned 180 degrees to allow for this. You want the rays to be focused on the bottom of the cooking area instead of the side and this will do the trick. A small grate was added just below the pinnacle of the receiver tripod. For now it has only been used to boil a pot of water. We’d like to see it grilling up some dogs but you’ll have to figure out a way to catch the drippings. We wonder if a transparent baking pan would block too much of the heat energy?
This is a great way to add purpose to neglected equipment. But if you’re serious about solar cooking you need something more along these lines.
Here is a classic project used to increase wireless signal strength. Cantennas focus using a waveguide very much like a magnifying glass focuses light. [Robert] made a Natural Light beer cantenna, pictured in the upper left. His approach used three beer cans, a paper towel holder, and a shower curtain rod. On the tipline, he noted a signal boost from 11Mbps to 54Mbps. This is certainly something we can hack together if our room lacks adequate signal. Read about parabolic and seeking versions after the break.
Continue reading “Various Cantenna builds”