Last Mile WiFi Over TV White Space

May 17, 2011 by 26 Comments

tv_wifi_gear

What do you do when you can’t afford broadband and no-cost WiFi is just out of reach?

That was the problem Rice University grad student [Ryan Guerra] was tasked with solving. A local Houston resident could barely tap into the free service offered in her area, so [Ryan] set out to extend the signal’s range using white space previously occupied by TV signals.

Using channel 29 which operates at 563MHz, his “Super WiFi” project utilizes standard WiFi protocols and can extend the signal’s reach up to a mile. The WiFi signals at the closest tower are piped through a prototype frequency translator, shifting the signal from 2.4GHz down to 563MHz, which is far better suited for long(er)-haul transmissions. The system does not use channel bonding just yet, so it is limited to using about 25% of WiFi’s maximum bandwidth, which is far better than no signal at all.

While the widespread practical use of TV white space will take some time to come to fruition, this is definitely a step in the right direction.

[Thanks Chris]

SCART Hack Automatically Selects TV’s AV Mode

April 26, 2011 by 21 Comments

We’re sure there’s still a lot of folks using their original Xbox either for gaming or as an XBMC device. If you ever owned one yourself you’ll remember that you can’t turn it on with a remote control. If you have to get up and push a button on the front of the black box, as least this hack will take care of tuning the television to the correct channel. That is, if you are using a SCART adapter to connect it to your TV.

[Karl-Henrik] figured out that mapping a voltage to pin 8 of a SCART port tells a TV that the port is active, and allows it to select the proper aspect ratio. Check out the Wikipedia SCART page to see that pushing 5-8V is the signal for a 16:9 aspect ratio, and 9.5-12V translates to 4:3. So he added an audio jack to the back of his Xbox and a matching one on the plastic case of the adapter. Now just tap into the wires on the power connector for the hard drive inside, connecting them to the newly installed jack. There’s a 12V and a 5V line, just choose the one based on the aspect ratio you prefer. He uses a jumper wire with the appropriate plugs on each end to make the connection. Now the TV will automatically tune to the correct AV input when the Xbox powers up.

TV Oscilloscope

March 7, 2011 by 25 Comments

Need an oscilloscope? Want to see the music? Don’t have money, but do have a old TV? Then this TV to oscilloscope mod may be right up your alley. Now don’t go running off just yet, when you’re working inside of a CRT device you are exposed to mains current, high voltage, and high frequency, so extra care needs to be observed .

If you have your rubber welding gloves, and have discharged all your fat capacitors (including the CRT) its pretty much the same magic trick as couple we have previously featured. Patch an amplified input signal into the vertical deflection coil and let her go, but this instructable features much more detailed instruction, and photos so you have a much better chance of replicating this (not quite lab grade) potentially useful device.

Join us after the break for a short video.

Continue reading “TV Oscilloscope” →

Stepper Directed HDTV Antenna

January 26, 2011 by 22 Comments

Credit: http://www.instructables.com/id/Computer-controlled-OTA-TV-antenna/

Broadcast TV has come a long way from adjusting the rabbit ears on top of the set just to get a fuzzy black and white picture. While nowadays there are often HD signals broadcast in most areas, it can often still be critical to redirect an antenna to get the best possible signal. By harvesting a stepper motor from an old 5 1/2″ floppy drive, and using a PC’s parallel port to control it, this adjustment can be handled automatically. Broadcast tower locations are easily found online, and once you have calibrated your stepper to face North, you are on your way to free HDTV reception.

What we would like to see is this antenna attached to a HTPC, and some kind of script to automatically direct the antenna for the best possible signal for the current channel. If anyone out there makes this happen, be sure to let us know.

Have You Ever Wanted To Be On (Internet) TV?

November 5, 2010 by 2 Comments

Are you an independent inventor? It might just be your lucky day. The fine folks at Independent Inventor TV, a new show currently filming for Revision3, is looking for home and garage based inventors to present their inventions for the camera. Currently they are based out of San Francisco, CA and are looking to film people in person, or by Skype if you are out of town.

To apply to be on the show, send an email to Independent.Inventor.tv(at)gmail.com with the details, photos, and videos of your inventions. The shooting date of the show is November 15th, so make sure to have all submissions in well before then. The selected inventors will get to meet the hosts, Comedian Jonah Ray, as well as fellow hacker [Joe Grand] (who is the creator of many of the DefCon Badges we have covered before). Be sure to let them know Hackaday sent you!

TV Out For TI Calculators Using The Link Port

October 30, 2010 by 19 Comments

Do people enjoy wasting 300$ on a bulky convoluted system, that only works for special “Teacher Edition” calculators, and is several years out of date; E.G. the TI-Presenter? [Benryves] certainly does not. So instead of purchasing a TI-Presenter, he made his own TV out system for the TI brand of calculators by using an ATmega168, a few passive components, and some clever code. The only draw backs being: you save 280$, it fits in your pocket, and it works for almost any TI calculator. Bias aside, the system does actually have a few caveats compared to the commercial edition, but the pros far outweigh the cons.

Hacking TVs In 1954

October 19, 2010 by 32 Comments

shaddap already!

This gem was published in Mechanix Illustrated magazine in may of 1954. AT that time, a remote control was the stuff of science fiction. This article shows the modern man how to modify his television to include a fancy button to stop all noise. This button, affectionately labelled the “SHADDAP” was marketed as a way to relieve the pain of long winded commercials. Basically, it cut the connection to the speaker, nothing super fancy. Is that an altoids tin as an enclosure?

[via BoingBoing]