cell phone shielding

[K8MHZ]

G

ood point. You should be able to jam signals in your own space.

The FCC doesn't agree and won't even let jails jam cell phone signals.

CFR 47 prohibits the intentional interference of any radio signal or communications. No exceptions.

There is some question as to if passive blocking is considered interfering. I say it is. To me it's obvious that the intent of the RF shield in question is to interfere with the signals of a cell phone. So far, the FCC has not cited anyone for using passive blocking methods, but has stepped in when jammers were used, even by the government itself. Schools have tried to be able to use jammers legally to no avail.

W. R. Hollingsworth retired as the head of the enforcement division of the FCC and Laura Smith has taken his place. She is being very aggressive about enforcement.

You all do what you wish, I prefer to let someone else be a test case.

So, no matter what others (most likely with NO background in radio and communications) say, you are better off to let someone else be the designer, hire the attorneys and fight the FCC if it comes down to that. Following designs you did not make should...and I say should bearing in mind today's litigious society, keep you out of the litigation food chain. And that's just on the front of the FCC....there still exists a civil case if, down the road, the customer feels the design you sold them isn't working as marketed.

This is NOT something you want to get involved with if you have no training or experience in the matter. Trust me.

 

[dereckbc]

Good point. You should be able to jam signals in your own space.

One would think so, but active jamming is illegal without written permission of the FCC like a school or prison. Passive measures are legal as there is no law stating it cannot be done. It is a lot like the NEC.

Now with that said for about $100 you can buy a jammer that will get the job done, just like a 100 watt CB. FCC will not investigate unless it gets complaints and a lot of them.

 

[K8MHZ]

One would think so, but active jamming is illegal without written permission of the FCC like a school or prison. Passive measures are legal as there is no law stating it cannot be done. It is a lot like the NEC.

Now with that said for about $100 you can buy a jammer that will get the job done, just like a 100 watt CB. FCC will not investigate unless it gets complaints and a lot of them.

Wrong. The FCC will follow up on just a single complaint. I have worked with the Detroit field office on an issue generated by a complaint from a single ham radio operator.

The first step is a notification and a request for a response. The notification will state that the infraction must stop immediately.

Since Ms. Smith took over, more complaints about illegal CB operation are being perused where not too long ago nothing was done about it.

Here are recent enforcement actions just as they affect the amateur radio service (both to and from, mostly to. Check out how many CB operators are cited)

http://www.fcc.gov/eb/AmateurActions/Welcome.html

As you stated, so far the FCC has not considered blocking to be intentional interference, but the rules are subject to interpretation and enforcement, both of which seem to change every time a new regime takes over. FWIW, the congressman that will oversee the FCC was just appointed last week and he is a ham radio operator. His interpretation of interference just may be different than his predecessors.

To err on the side of caution is most prudent, especially for the next couple years while the issue of cell phone control is working it's way through the system. What is fine and dandy today could change in the blink of an eye with a single precedent setting case.

 

[scottp628]

wired an xray room a number of years ago, lead lined sheet rock work very well. wrapped all electrical boxes with lead, all joints and seams were covered in lead tape or buttons for screws. lead lined doors and door frame. did stop cell service. sounds like a secure room in a business or temple. suggest you have some one else design, you build. good luck.