arduinos talking back and forth with walkie talkies - Page 1
Forum section: electronics / general

author: cowboy303
author_rank: Regular Contributor
timestamp: August 08, 2012, 01:56:40 pm
content: Hi Guys,I've been working on a remote control truck. And I was thinking as for a remote what if I had an arduino in the remote and an arduino in the truck and used walkie talkies to talk back and forth if I had a walkie talkie on TX and RX of both arduinos.Just a though. What do you think.

author: george graves
author_rank: Super Contributor
timestamp: August 08, 2012, 02:36:11 pm
content: It's a very good idea! (I've thought of it as well, or something like a semi-remote weather station or something.)One thought would be DTMF tones - If you google a bit you'll find projects that will both decode and generate the tones on an arduino - and I believe there are chips that will do it outside of the arduino as well.Another though might be a really low baud rate version on old telephone modems? I'm sure there's tons of info on that.

author: johnboxall
author_rank: Unknown
timestamp: August 08, 2012, 11:08:31 pm
content: Quote from: cowboy303 on August 08, 2012, 01:56:40 pmEasily done. This person has done it in one direction, with some mods you could set up a simplex system quite easilyhttp://bit.ly/NH8zXd

author: olsenn
author_rank: Frequent Contributor
timestamp: August 08, 2012, 11:25:56 pm
content: You can buy premade modules that are compatible out of the box with Arduino, which will facilitate this for you. They range from simple RF links (various frequencies, usually sub-1GHz) to 2.4GHz 802.11 and Blutooth transceivers. They will cost you about as much as the Arduino, each, but they will take care of all the hard parts for you and offer quite reasonable range and capabilities.If you wish to design the radio transmitters yourself, you may want to try building some crystal stabalized transmitters/receivers/transceivers, and using FSK for modulation to send data. Unless you are skilled at RF design, they will not operate as well as professionally made units (smaller range, slower data rate etc) and may violate some FCC regulations if that's important to you, but it will get the job done and be much cheaper in the long run.

author: westfw
author_rank: Super Contributor
timestamp: August 08, 2012, 11:30:10 pm
content: regulation-wise, I'm pretty sure it's not legal to use walkie-talkie radio bands for "remote control."With the number of license-free wireless devices you can buy off-the-shelf, it's hard to remember that the radio frequency spectrum is pretty strictly controlled WRT which frequencies can be used for which sorts of applications, but the regulations are still there.

author: olsenn
author_rank: Frequent Contributor
timestamp: August 08, 2012, 11:47:15 pm
content: QuoteCheck out the FRS bands (27MHz); there are power restrictions imposed, but you would be hard pressed to exceed them without tuning your antenna specifically to do so (adjusting VSWR, length, type, etc) and using some more complicated design procedures. Also, the CB (Citizen Bands) are not regulated anymore, but you'll likely get interference from truckers etc. Some frequencies simply aren't even alocated by most federal regulation commitees, so if you use one of those frequencies, although you'd technically probably be breaking the law, they would likely not be checking for unauthorized use on those frequencies or even care, and you would be almost guarenteed to not encounter any interference with other signals.Just stay clear of the HAM (amateur radio) bands... those bastards treat FCC regulations like their bible. They would probably have nothing better to do then to personally use their high-end equipment to track down your location, record your transmissions, and pass them off to the government as if they were personally responcible for "bringing justice" to offenders. They're all old, overweight virgins!

author: Wartex
author_rank: Frequent Contributor
timestamp: August 09, 2012, 12:08:22 am
content: Quote from: tronixstuff on August 08, 2012, 11:08:31 pmData over FRS and GMRS is illegal.

author: notsob
author_rank: Frequent Contributor
timestamp: August 09, 2012, 12:31:48 am
content: Perhaps have a look at what's already available in the telemetry section at diydrones.com