Not an expert on these phones, but I did spend 10 years of my life developing software for public safety radio systems.  I can't think of any reason why the Becom base station would communicate with the phones when the phones are not in use.  Unlike a cell phone where the mothership needs to know which site it is connected to, the Becoms don't have multiple base stations so I can't see the point of any off-line handshaking.

Thanks Stan - in the articles I've read and on YouTube there seems to be an opinion that these are on all the time and communicating with each other 24/7 - I agree with you as I can't see why it would be transmitting unless it needs too - I've ordered an EMF meter to put my mind at rest and will let you know what the results are.

I'm quite interested as I practice Amateur Radio and this started when I had really bad interference which turned out to be caused by an LED lightbulb in my hallway - quite a way from the Radio room.

Thanks Stan - in the articles I've read and on YouTube there seems to be an opinion that these are on all the time and communicating with each other 24/7 - I agree with you as I can't see why it would be transmitting unless it needs too - I've ordered an EMF meter to put my mind at rest and will let you know what the results are.

I'm quite interested as I practice Amateur Radio and this started when I had really bad interference which turned out to be caused by an LED lightbulb in my hallway - quite a way from the Radio room.