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FRS radio -> ip phone.... what do you think — Parallax Forums

FRS radio -> ip phone.... what do you think

mcstarmcstar Posts: 144
edited 2006-05-28 23:28 in Propeller 1
I'm chomping at the bit to get my propeller.· I placed the order on Wed for a demo board, but apparently the units are out of stock for a couple weeks.· In the meantime, here's an idea I'd like to open to the forum for comments.· Please chime in if you know have specific ideas for makeing this idea work, or know of limitations or regulations to be aware of.

Here's the idea.· I've started noticing recently that some of the small hand-held FRS radios available for public use (no liscense required), have ranges of 8-10 miles.· Since I currently do just about everything during the week within 8 miles of my home, my thought was, "what if·I could use an FRS radio as a replacement for my cell phone".· To do this, I'd need a way to "connect" my frs radio to my ip phone and send controlling signals to it·via the radio.· So, how realistic do you think it would be to use a propeller on both ends as an interface driver·and to send commands the ip phone?· Basically we'd need to have a keypad and perhaps a display connected to the propeller.· It would have to Frequency Modulate a carrier wave onto the FRS radio signal that encodes the keypad data handles the digital communication protocol.· This would be DeMuxed on the other end by the recieving propeller and turned into data that could feed into the ip phone box (over ethernet, maybe through a pc via it's sound card).· Once the·ip phone·connects, the audio would be passed through·to the·FRS radio·just like it is normally.· The only draw back is the walkie-talkie style·half-duplex operation, but I think I'd be OK with that to save $150/month in cell phone charges.

Does anyone else think this could work?· I was thinking that he propeller's counter/pll should be able to handle the Mux and Demux of the digital command codes onto the audio, does this sound feasible?· Does anyone know what the highest freq those FRS radios can handle is?· It would be nice to mux a frequency high enough that it's inaudible.


Post Edited (mcstar) : 5/26/2006 2:12:36 PM GMT

Comments

  • Harrison.Harrison. Posts: 484
    edited 2006-05-26 15:20
    I believe the FRS band is limited to 1-2 miles (max 500mw), you may get better than that due to more sensitive receivers, etc.· You are probably talking about GMRS which lets you go somewhat farther (~12 miles, max 2watts).· GMRS requires something like a $80 dollar / 5·years·licensing fee.

    You also need to check the legal limits of what kind of data / audio you can send over these bands.· It might be illegal to send dtmf and other control signals over these bands.

    Other than that, the idea should work.· (Sorry for being pessimistic, but I would hate to see someone get in trouble for breaking laws they didn't know existed).

    Harrison
  • mcstarmcstar Posts: 144
    edited 2006-05-26 17:20
    Acutally, that's the sort of comment I was looking for.·· If the idea is feasible, I'll work on it.· I've·confirmed what you said about the GRMS·vs FRS as well.· Does anyone know what the highest freq that can be transmitted by GRMS is?· Is it above audible?
  • Kevin WoodKevin Wood Posts: 1,266
    edited 2006-05-27 14:58
    Technology-wise this is possible, but I don't think it's legal per FCC regulations.
  • cocokiwicocokiwi Posts: 75
    edited 2006-05-28 23:28
    mcstar said...
    I'm chomping at the bit to get my propeller.· I placed the order on Wed for a demo board, but apparently the units are out of stock for a couple weeks.· In the meantime, here's an idea I'd like to open to the forum for comments.· Please chime in if you know have specific ideas for makeing this idea work, or know of limitations or regulations to be aware of.

    Here's the idea.· I've started noticing recently that some of the small hand-held FRS radios available for public use (no liscense required), have ranges of 8-10 miles.· Since I currently do just about everything during the week within 8 miles of my home, my thought was, "what if·I could use an FRS radio as a replacement for my cell phone".· To do this, I'd need a way to "connect" my frs radio to my ip phone and send controlling signals to it·via the radio.· So, how realistic do you think it would be to use a propeller on both ends as an interface driver·and to send commands the ip phone?· Basically we'd need to have a keypad and perhaps a display connected to the propeller.· It would have to Frequency Modulate a carrier wave onto the FRS radio signal that encodes the keypad data handles the digital communication protocol.· This would be DeMuxed on the other end by the recieving propeller and turned into data that could feed into the ip phone box (over ethernet, maybe through a pc via it's sound card).· Once the·ip phone·connects, the audio would be passed through·to the·FRS radio·just like it is normally.· The only draw back is the walkie-talkie style·half-duplex operation, but I think I'd be OK with that to save $150/month in cell phone charges.

    Does anyone else think this could work?· I was thinking that he propeller's counter/pll should be able to handle the Mux and Demux of the digital command codes onto the audio, does this sound feasible?· Does anyone know what the highest freq those FRS radios can handle is?· It would be nice to mux a frequency high enough that it's inaudible.
    ···· there are WIFI phones which ARE Voip , all you need are any LOCAL WIFI connection within that area, get a copy of

    ···· Pop Science June page 26,

    ··· Vonage UTSTARCOM F1000 WI-FI HANDSET·· $130·· 5 HRS TALK TIME 50 HOURS STANDBY !

    ·· ·GET INTO RANGE AND· start talking for free!·don,t know if you can use the same # as home though!

    ·· ·BUT! you can take it anywhere there is WI-FI, like any hotel,even overseas and call home.idea.gif
    ··· I have Vonage, But I don,t travel much! As for your Idea those radios Do not have the range,11 miles is line of sight, That is wittled down
    ··· to around 2 blocks with all the houses around,and thats with GMRS the more powerfull channels that one is supposed to pay for.

    ··· one is supposed·to have a hill somewhere with a repeater on it so one can get more mileage! I have a bunch of those radios!

    ··· Cheers Dennis

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    http://people.delphiforums.com/cocokiwi/Image/picture.jpg

    Post Edited (cocokiwi) : 5/28/2006 11:43:31 PM GMT
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