Radiate Your Rocks

WOW now I have seen it all.

Jonathan, what exactly do you mean with no RF protection?

Andy, the FCC sets general public and occupation exposure limits for RF emissions. Major sites like this often pump signal that can exceed the general public (and sometimes the occupational) RF limits. The FCC requires that any areas exceeding the gen-pop standard be secured to prevent public access.

Who might be members of the public at this site? Interestingly, other RF engineers/techs who are NOT aware of the specifics of the emissions for a nearby site are considered to be unable to protect themselves from excessive RF emissions, thus they are gen-poppers.

I'm a gen-popper since I don't know the RF emissions specifics for these sites even given my vast knowledge of RF from cell sites! :browani:

jlk

Ah, that clears it up and is actually what I thought. California is weird; one one hand they want to disguise everything, but then if you look at this example, there's no RF protection. You could say the same, however, for sites that are on low towers and don't have a big fence around them. I might be able to snap a pix of one like that- I don't think there's a lot of RF protection there either.

I'm familiar with occupational/public standards of radiation protection and I'm sure that California requires it for RF just as any other state. It also may be a federal standard for RF protection in which case the states are usually in agreement.

An RF engineer can be more specific but antennas that are low on a tower radiate laterally (perpendicular to the face of the panel) and not directly downward so the RF is not as high as you'd think directly below an antenna compared with being a short distance away and at the level of the antenna.

G: The RF emissions standards are found in FCC OET Bulletin 65 (see http://www.fcc.gov/oet/rfsafety/). While you're there, download the FCC's guide to local government officials which I co-authored.

The FCC completely occupies the field of RF safety in the U.S., thus no state or local government can adopt any RF standards of their own. Most government simply require a demonstration that the federal standards are being or will be met.

You're comments about emissions being on the horizontal plane are correct, but some antennas do provide for either an electrical or physical downtilt of upwards of 15 degrees. If the downtilt is achieved physically, the antenna is installed on a pivot mount. For an example, look at the top bracket in: http://gallery.wirelessadvisor.com/displayimage.php?imageid=1192. If electronically, there's no easy way to tell. Also, some antennas are remotely controled to vary the downtilt.

jlk

Thanks for the links. It looks like interesting reading and I will get to it at some point.

Nice pun, Jay