Hack 33 Why Your Cell Phone Doesn t Work There

Trouble getting a signal? Google maps and the FCC database can help.

I live almost in the shadow of a 30.2-meter cell phone tower, and I have to go out on the porch to get decent reception. What is up with that? I know the exact height of the tower, thanks to Mobiledia. You can go to its site at http://www.cellreception.com/towers/index.html and browse for cell towers by city or state. When I look up Sebastopol, California, I get the map in Figure 4-15.

I live near the S in Sebastopol, so you'd think I'd have pretty good coverage 2.5 blocks from the tower. Clicking on the overlay marker brings up information on the owner of the tower, as shown in Figure 4-16. So my problem appears to be that there is a tower, but my cell provider doesn't have gear up there.

Figure 4-15. Cell towers near Sebastopol, CA

You can click on the overlay marker because marker labels are HTML and support links. Mobiledia defines marker text with this line of code:

var html="

<a href="http://www.cellreception.com/towers/details.php?">" + name + "</a>

" + address + "

" + city + ", " + state;

This builds a URL that calls a script on its site with more details. This is an example of how you can include links and arbitrary HTML in pop-up markers. Mobiledia uses the FCC database of antennas, and as explained on the site:

The FCC does not require every antenna structure to be registered, and the map may not list all the towers in the area. Additionally, many carriers have sold their tower assets to third party companies, and leasing agreements are unknown. If this is the case, the best way to determine carrier coverage is by reading comments in the local area.

So it is possible that my provider rents space on the tower, but since the best way to determine coverage is to read the comments, I think it is safe to just assume that my calls don't go to the most convenient tower.

On the right sidebar is a "Cell phone reception search." Enter a ZIP Code and it pops up a reader forum on reception, or in reality more likely the lack of reception. You can also search for dead spots and add your own reviews.

Figure 4-16. Ah, that would be why I don't have service

Another neat feature of the site is that you can get HTML that lets people search the reception and tower databases from your site. Just go to http://www.cellreception.com/add/index.html and fill out the form, and they send links to an HTML form that you can embed in your own web page.