Smart phones, cell phones--do they pulse?

Hoping someone can help me with this.  I was househunting yesterday and the realtor had left her cell phone in her car (turned on).  While in the house I picked up a brief pulse on my electrosmog detector twice, both times while in the corner of the house near the driveway.  The Wifi and cordless phones were turned off in the house, so I am trying to figure out where this pulse was coming from.  The nearest tower is at least a mile and a half away.  Could it have come from the phone in her car?  Does anyone know if these newer generation phones send out periodic pulses like this, and would they reach that far into the house if her car was in the driveway?  Or is it more likely that it came from another source?  I could find no other explanation inside the house for the noise I heard on my meter.  I am doubtful it came from the nearest tower since it's so far, but who knows?  Any help would be appreciated.
Thanks,
Mary

> Does anyone know if these newer generation phones send out periodic
> pulses like this

I think all cellphones send out periodic pulses when turned on.  Some
even send out periodic pulses when turned off.

Marc

Hi Mary,

Yes, and yes.
I can pick up individual cell phones 1/2 mile away on the Acoustimeter,
when not drowned out by a cell tower.
And they do send out "Here I am" periodically, which probably leads to
"any new messages?"

Stewart


epicsconartist wrote:
>  Could it have come from the phone in her car?  Does anyone know if these newer generation phones send out periodic pulses like this, and would they reach that far into the house if her car was in the driveway?
>
>  

Marc Martin wrote:
> I think all cellphones send out periodic pulses when turned on.  Some
> even send out periodic pulses when turned off.
>  

Yes, Off is not off. It must be in airplane mode to be silent.
Stewart