Want to read Slashdot from your mobile device? Point it at m.slashdot.org and keep reading!


Forgot your password?

Cell Phone Reception Hack 142

New Breeze writes "Has this ever happened to you? Just when you need to make a phone call, the bars of reception are scant to none. But Graeme, who writes a blog called 'Earth: Mostly Harmless,' gives us hope. Succeeding where most would quit, he chronicled his ingenuity in a post titled 'How I got mobile phone reception where there was no signal.'" Update: 08/01 14:31 GMT by T : Note: Credit for this story belongs to Mike Yamamoto, who wrote it for CNET's News.com.
This discussion has been archived. No new comments can be posted.

Cell Phone Reception Hack

Comments Filter:
  • site down? (Score:1, Informative)

    by nyquil superstar ( 249173 ) on Monday July 31, 2006 @05:57PM (#15820945)
    Is the linked site down for anyone else? Already?
  • Re:Short version: (Score:5, Informative)

    by ElectricRook ( 264648 ) on Monday July 31, 2006 @05:59PM (#15820969)
    I use the old three watt bag phone, gets great reception, costs US$19 per month, never rings unless I plug it in, which I never do. Clear as a bell, even if I'm out in the woods. Reception not too good in some canyons.
  • Mirror (Score:4, Informative)

    by andyring ( 100627 ) on Monday July 31, 2006 @05:59PM (#15820970) Homepage
    It's getting pretty slow. Here's a mirror [andyring.com].
  • Article text (Score:1, Informative)

    by Anonymous Coward on Monday July 31, 2006 @06:06PM (#15821034)
    How I got mobile phone reception where there was no signal
    Posted at 20:30 by Graeme
    Categories: Uncategorized

    (Or, to be more accurate, where 20ft of solid stone was blocking line-of-sight to the nearest transmitter.)

    I just got a Nokia E61 on T-Mobile. When I signed up, I knew that the signal was really weak in the back of our house - the building forms a large square, and my bedroom faces into the centre of the square. I could get a signal in the living room (just), but wouldn't it be great, I thought, not to have to go through there every time the phone rings. Although outside my house full-strength UMTS signals are readily available, the building's construction prevents them diffracting into the internal 'courtyard'.

    All I needed was enough reception to receive and send SMS messages. I have home WiFi for data access, and I can potentially make calls over that too. I planned to aim for UMTS reception rather than GSM since: a) I didn't know which GSM frequency to aim for and b) E series Nokia phones maintain their batteries better if they have UMTS signals (otherwise they constantly search for a UMTS signal).

    I tried two car-type external antennas that I got via eBay - but unfortunately the gain on both of these was just too low (barely even compensating for the losses in the cable running to the phone). Also, neither were sufficiently directional to catch enough of the reflected signal to give me anything to work with.

    The first step was the figure out what the extent of the problem was. I located my nearest T-Mobile base station using the government's Sitefinder service. This also confirmed the frequency that the transmitter used - 2100Mhz. This is the standard frequency for UMTS (i.e. 3G) services in Europe.

    By drawing a line between the transmitter's location and my building in Google Earth, I was able to confirm the approximate distance and angle of the signal I needed to catch.

    Buying a directional antenna wasn't really an option - for a start, they are expensive - and anyway I couldn't be sure that such an antenna would actually help. If it didn't, I'd have wasted £60-£100.

    However, in an incredibly geeky flash of inspiration, I realised that there really isn't much difference in operating frequency between WiFi (around 2.4Ghz) and UMTS (2.1Ghz). And there are loads of different clandestine WiFi antenna ideas floating around the Internet. If I could find an easy-to-build directional WiFi antenna, perhaps I could reverse-engineer its dimensions and adapt it for 2100Mhz use.

    So I set about the task. I decided on the biquad antenna type, as it's fairly compact and easy to build, yet provides decent (10-14dB) gain and is quite directional. My primary sources of information were the many WiFi biquad and double bi-quad antenna tutorials and blog entries, such as: Engadget's; Trevor Marshall's tutorials. More can be found on my del.icio.us page for the tag 'antenna'.

    Both WiFi and UMTS operate in microwave frequencies - however, there's a substantial difference between the middle WiFi channel (around 2.4Ghz - what people usually tune their WiFi antennas to in order to give a good amplification factor across the channel range) and UMTS' 2.1Ghz. To my knowledge no-one has built a homebrew biquad UMTS antenna before, so there wasn't much to go on. What also didn't help was that most WiFi biquad tutorials just give you the measurements verbatim - not the calculations of formulae.

    Having done no physics since school, my expertise in antenna building is poor to say the least. Still I did realise a few things about most of the designs floating around the Web: all of the dimensions were multiples of the wavelength at 2.44Ghz (122mm or 0.122m). So then, I just needed to figure out the multiplication factors in each case and I was sorted.

    My list is as follows: ( = wavelength)

    * Emitter wire total length: 2
    * Emitter 'square' side length: 0.25
  • by www.sorehands.com ( 142825 ) on Monday July 31, 2006 @06:19PM (#15821112) Homepage
    Not to rain on this guy's parade, but well duh! If you put up a bi-quad antenna, a circular polarized quad bay or 8 element yagi you would get a better signal. Of course he could have used a pringle can [oreillynet.com] for a 12db gain.
  • by tacokill ( 531275 ) on Monday July 31, 2006 @06:20PM (#15821120)
    So, I get to /. and I start to scan the articles. The usual stuff...12 dupes and a few new stories. I get to one called Cell Phone Reception Hack

    Cool. I'll check that one out.

    I pull up the list of comments and I click on the link to the article. I read the article from start to finish and having consumed the literary words on the page, let me be the first to post...

    Read my lips: Antenna != hack

    This is in no way, shape, or form a hack. It is a guy building an antenna. It's only been done by thousands of other ppl over the last 50 years. But yea, let's run the story anyway and call it a 'hack'.

    Well, it's not.
  • Re:Bars (Score:3, Informative)

    by steveo777 ( 183629 ) on Monday July 31, 2006 @06:23PM (#15821131) Homepage Journal
    I get that kind of crap too. I live in the middle of a metro area and I get almost no signal in my house. I had to buy a bluetooth headset just so I can leave my phone in an ideal position for signal. Pisses me off. Not like the phone companies care. Half the time when I dial it says 'connecting' for 15 seconds and then the bars dissappear and I get the main screen on my phone back like nothing happend. This has happened to me with three seperate phones, Two Motorolas and a SonyEricson. Also Verizon and Cingular as carriers. So you're not alone my signal-deprived comrade.
  • Re:Short version: (Score:5, Informative)

    by vonwilkenstein ( 817078 ) on Monday July 31, 2006 @06:42PM (#15821233)
    Enjoy it now while it lasts. FCC is allowing carriers to pull the plug on AMPS soon. We ( as in the carrier I work for) are vastly de-growing the AMPS network to a barebones network with BARE minimum capacity. Also as this is occuring, there have been cells that were just removed altogether eliminating AMPS coverage altogether. I do agree however, three watt bag/install phones are the shit for voice calls.
  • Re:Short version: (Score:3, Informative)

    by gfilion ( 80497 ) on Monday July 31, 2006 @06:54PM (#15821297) Homepage

    Use an external antenna. A lot of phones still have connectors for those, so no hacks required there.

    Obligatory karma whoring: Here's a good place to buy one. [wilsonelectronics.com]

    For CAN$50 I got myself a mag mount 5 dBi external antenna. [wilsonelectronics.com]

  • by liquidpele ( 663430 ) on Monday July 31, 2006 @07:04PM (#15821354) Journal
    You can always find some stuff on hackaday.com [hackaday.com] like this /. story.
    If you wern't already aware anyways.
  • by IvyKing ( 732111 ) on Monday July 31, 2006 @09:35PM (#15822139)
    RG-58 is high quality cable when compared to RG-174 - but a better choice in that size would be RG-223. RG-6 is 75 ohm, and coaxial cables are usually referred to as unbalanced lines as the outer conductor is usually at ground potential.
  • Re:Sitefinder (Score:4, Informative)

    by plover ( 150551 ) * on Monday July 31, 2006 @10:14PM (#15822301) Homepage Journal
    I found this FCC site [fcc.gov] which allows you to search for registered towers. After you find towers (in a particular city, for example) you can click on the individual tower (lat/lon data is provided here) then the "map registration" button will bring you to a Tiger map of the tower.

    Then I found out that someone has a google maps interface [cellreception.com] to the same data. Screw that FCC site! :-)

  • by toybuilder ( 161045 ) on Tuesday August 01, 2006 @12:18AM (#15822846)
    If you are just marginally out of cell phone range, you can just buy an antenna and appropriate connector cable from Wilson Antenna or from Radio Shack. I've had "2 bar" situations go to 5 bars, and went from "no service" to 1 to 2 bars in a basement of a concrete building. The antenna and connector cable will set you back about $30-$40, but is probably plenty good enough if you know that the signal is just barely making it.
  • Re:Short version: (Score:3, Informative)

    by plover ( 150551 ) * on Tuesday August 01, 2006 @12:40AM (#15822923) Homepage Journal
    Hmm... from your FA:
    Cingular has been working for years to phase out these technologies in favor of GSM (Global System of Mobile Communications), a newer technology that is the world's most popular wireless standard.
    I didn't get the memo. When did the acronym GSM get hijacked by illiterate Americans? I always thought it stood for "Groupe Spéciale Mobile"?

    Of course, I hope the French are pissed. :-)

  • by Kadin2048 ( 468275 ) <slashdot.kadin@x[ ].net ['oxy' in gap]> on Tuesday August 01, 2006 @12:50AM (#15822967) Homepage Journal
    Unfortunately, it's just a "How to _use an antenna_" article.

    Yeah, pretty much.

    I don't want to be too hard on the guy, because it sounds like this was his first antenna project, but the whole article just makes me a little sad. What he did isn't even all that hard, and if he had done a little more searching around he would have found literally thousands of pages and hundreds of articles, complete with formulae and schematics, on how to build antennas of this type.

    There's an amateur radio band located just above (and IIRC overlapping slightly with) the 2.4GHz ISM band. There's tons of antenna construction resources; the American Radio Relay League has two volumes written about the topic [arrl.org]. (Although it covers a lot more than just antennas, admittedly.) Although I don't own the book, I'd bet that most of those articles probably have equations for scaling the dimensions to particular frequencies, so it would be trivial to do what he was attempting. (And a quite likely a violation of FCC rules, but that's another story.)

    On a more general note, it's a little sad to see how little of a connection there is between the radio "hacking" community and the computer one. Perhaps it's due to there being a generational gap in there, but I've never met two groups of people that have as much in common, philosophically, as computer hackers and ham radio tinkerers. When I read articles like TFA, where the author says "To my knowledge no-one has built a homebrew biquad UMTS antenna before..." it just really underscores how poor a job the amateur radio community has done in connecting with computer geeks. The topic at hand here isn't something breathless and new, it's well-understood to the point of probably being boring. But because of the lack of connection between the two interest groups (even though, as in this case, they have a lot of common interests even if they don't realize it), we have computer geeks painfully reinventing the basics of antenna design, and we have ham radio operators who haven't in some cases even figured the Web out completely, much less how to use it to collaborate.

    That's not to say that there aren't computer geeks who are into ham radio and vice versa -- the number of radio-related software projects is testament to that (as am I, and others here on /.), but it's a lot less than you would think given how much each group could stand to gain and benefit and learn from the other. There's some stuff being done that honestly is breathless and new, on the cutting edge of both radio communications technology and information/computer technology, but there's a shortage of people with the combined background to contribute. How much further along would we be, if both groups were't wasting so much time reinventing each others' wheels?

"I will make no bargains with terrorist hardware." -- Peter da Silva