Mobile phone signal simulator

Discussion in 'The Projects Forum' started by DarkMavis, Aug 26, 2014.

  1. DarkMavis

    Thread Starter New Member

    Aug 24, 2014
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    Hey, I was wondering if it's possible to make a cheap device that mimics the electromagnetic radiation emitted by a mobile phone. It doesn't have to actually resemble a signal carrying any information, just be of a similar strength and frequency to a mobile phone making a call. Is there a single unit you can buy that does this for test purposes?
     
  2. wayneh

    Expert

    Sep 9, 2010
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    Sure, it's called a cellphone. Go on craigslist or e-bay and you can find them for almost free.
     
  3. DarkMavis

    Thread Starter New Member

    Aug 24, 2014
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    I want to e able to activate it by pushing a single button. I also don't want the signal sounding like morse code when it's picked up by audio circuits. I just wanna push a button and generate a single, constant frequency in tghe same range as from a mobile phone
     
  4. MikeML

    AAC Fanatic!

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  5. DarkMavis

    Thread Starter New Member

    Aug 24, 2014
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    Not on this, no! I assume it can be done for less. After all, it frequently IS...in mobile phones.
     
  6. alfacliff

    Well-Known Member

    Dec 13, 2013
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    cell phones sont use one single frequjency, the hop around to find clear chanels and active systems.
     
  7. DarkMavis

    Thread Starter New Member

    Aug 24, 2014
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    Well...any frequency within the range they use would be fine. Let's just say something that will generate a UHF signal at 1 or 2 GHz
     
  8. Veracohr

    Well-Known Member

    Jan 3, 2011
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    It's just a radio signal, so you can find/build a radio transmitter at your desired frequency. I think 0.6W is a typical transmitter strength, but you might want to research that. However, if you really want to simulate the signal frequency/strength relationship, you would need to use a similar modulation scheme as current phones rather than transmitting at a single frequency.
     
  9. wayneh

    Expert

    Sep 9, 2010
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    That would be the power button of the cellphone. That would turn on the radio. Or you could toggle a smartphone in and out of "airplane mode", which disables the radios.
    I only get that type of short range interference when the phone is receiving a digital message, for instance an e-mail. I think if you're using an old cellphone without an account, it won't generate any of that interference.
    As noted, that's not what cellphones really do.

    Maybe it's time to talk about what you are really wanting to accomplish?
     
  10. THE_RB

    AAC Fanatic!

    Feb 11, 2008
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    Like bypassing the forum rules on building cellphone jammers? ;)

    Just a wild guess.
     
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  11. sirch2

    Well-Known Member

    Jan 21, 2013
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    I seem to hear that kind of interference when a call is being initiated. I guess it is something like the radio starting at full power and backing off to a lower level as it negotiates with the cell tower.

    Many years (decades!) ago when mobile phones were bricks and we had CRT monitors, the guy who sat at the desk that backed on to mine had one of these bricks and I could tell he was about to get a call because of the interference on my monitor.
     
  12. wayneh

    Expert

    Sep 9, 2010
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    Hadn't even thought of that! Could be what we're talking about.

    I just can't grasp the project when the task is to simulate a cellphone radio, except for behaviors X,Y&Z that a genuine cellphone radio - something that is free to obtain - normally exhibits.
     
  13. DarkMavis

    Thread Starter New Member

    Aug 24, 2014
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    No, much as cell phone users annoy me, should it get to the level where I want them to stop, I think it will be far more satisfying to physically take their phone off them and smash it over their skull. At the moment, though, I'm happy to let them walk off cliffs, down wells, and into roads because they are too busy talking to all the people who are nowhere near them.
    Let's forget the cell phone thing, then. The reason I mention them is because, currently, a cell phone is the best thing I've found to accomplish what I want. Namely to set off a cheap Kii industries EMF meter from the greatest distance possible. I've used large pulsed coils, and relays wired as buzzers but the effect can never be detected from more than a few feet. A mobile phone, however, sets the things off from a LONG way off. However, you can tell by the way the reading dance up and down that it's a phone.
     
  14. DarkMavis

    Thread Starter New Member

    Aug 24, 2014
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    So, I did a quick search and found a 433mhz tone generator/transmitter used for tracking crashed model planes I think that will do the trick without jamming anybody's cell phones. So don't worry; y'all can still talk about lame movies on Facebook while walking from A to B

    Or is there a better way?
     
    Last edited: Aug 27, 2014
  15. THE_RB

    AAC Fanatic!

    Feb 11, 2008
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    Politeness and respect are two better ways, when you want people to take their time to help you.

    But feel free to go with whatever works for you. :)
     
  16. wayneh

    Expert

    Sep 9, 2010
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    Hahaha, so you want to simulate a ghost?

    It's hard to tell what the ideal solution would be, without experimental results. The ads for that device mention low frequency fields but don't mention radio frequencies that also give a response.

    Have you tried things like garage door openers, baby monitors, cordless phones (which used to be very similar to baby monitors), walkie talkies and so on? I'm thinking if you can identify consumer devices that give the right result, you'll have an inexpensive solution. No point in building your own wheel.

    There are a lot of experimenters playing with GSM radios in their projects. I wonder if you could use one of those, but just turn it on to transmit without any data (or just a tone?) being communicated.
     
  17. DarkMavis

    Thread Starter New Member

    Aug 24, 2014
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    Niooo. I was mocking cell phones in general, and the way people are glued to them. I wasn't mocking any individual other than all the millions of individuals who can't take their eyes off their phones. Ugh! I revived a necro'd thread to say that! If someone wants to close it, feel free,
     
  18. GopherT

    AAC Fanatic!

    Nov 23, 2012
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    It's your thread, you are allowed. As for hurting feelings, @THE_RB hasn't been around in a while.
     
  19. DarkMavis

    Thread Starter New Member

    Aug 24, 2014
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    Are you sure? I can't seem to figure out how. I looked in the thread tools and the options dealie down the bottom. I'll just let it go back to sleep
     
  20. GopherT

    AAC Fanatic!

    Nov 23, 2012
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    I meant that you can post to it any time you like. Only Moderators can close it but they need a reason, generally.
     
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