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Using a Cellphone in a Basement?
Nimsoft asks: "I recently moved into a basement flat and as a result I get no cellphone coverage in there. This is incredibly frustrating as my cell provider is so much cheaper than landline offerings I rely on my cell as my primary means of telecommunications. I can pick up a signal the second I step out of my front door and friends on other networks can sometimes pick up a weak signal within my flat. What would the geek solution (must be cheap!) to this issue be? Would attaching a larger antenna to my phone work, or can I hack together some sort of repeater and put an antenna outside somewhere?" While thousands of offers of repeaters and signal boosters are only as far away as the nearest Google search, what recommendations or experiences would you care to share on the subject?
I have a similar situation. Except my office is in the basement. Anyway, I use Vonage.
I have my cellphone set to conditionally forward to the vonage line. By that if I don't answer, instead of going to voicemail, it goes to the Vonage line. I use the Vonage voice mail. IMHO it is better because you can check the VM online via a web browser and other nifty features that are better than the cellphone.
-MS2k
Back in the day (when I was more involved with Ham Radio), we would use a passive repeater to fill in dead spots. A passive repeater is simply two antennas connected by a piece of coax. One antenna is placed where it will receive the desired signal well, the other is placed where you want to improve the signal (in this case, the basement).
Seems simple, but there are a couple of things to consider. First, you will have to know which band your cell phone is using at your house. The two likely choices are around 890MHz and around 1800Mhz (I am doing this from memory, so look it up). Then, the simplest antenna to make is a vertical dipole. Each antenna is two pieces of coat hanger, each piece cut to a quarter wavelength of the frequency you are using.
The next thing to consider is that all coax has loss. At 1.8 Ghz, you could easily be looking at -10db per 100 feet for average coax. So, make sure that you use the best coax you can find (it will be more expensive, but worth it) and keep it as short as possible.
If you are not getting enough signal with this arrangement, you can get fancy and build a better antenna for the end that gets a good signal from the cell tower. Two more pieces of coat hanger will let you build a three element directional array. Mount the coat hanger pieces through 3/4 inch PVC. You will need something like the ARRL Antenna Handbook to get the correct lengths for the pieces, and the distance between them. Since this kind of antenna is directional, you will need to point it at the cell tower. Also, remember to keep the elements vertically oriented, not horizontal like a TV antenna.
Good luck
it is most likely that your cell phone has an antenna connector on it somehwere (most do, they are usually covered by small grey plastic plugs). i would find out what kind of connector it takes, and get a cell antenna (the kind people use in cars should work fine) that will adapt to it. signal loss with coax is a significant concern, so you will want to keep that link as short as possible, another way around this is to use a high-gain antenna deisgn, that should help compensate for the signal loss from the cable.
Cogito Eggo Sum, I think therefore I'm a waffle
Don't some car 'hands free' kits include an outside arial?
If so, the obvious thing to do seems to be to get one, and put the arial somewhere where it gets a signal.
Just my $0.02,
Michael
"Goodness me, how unlike the FBI to abuse the trust of the American public." -- The Onion
http://www.4cellular.com
^ These guys sell a repeater that would suit your needs.
"A learning experience is one of those things that says, 'You know that thing you just did? Don't do that.'" - DNA
Universal Antenna.
I'm tired of bombing the universe
Several companies make products like this one which let you stick a cell phone in a cradle and hook it up to one or more wired telephone sets. Just set one of these up at your entry and wire it down to the basement.