Using the AC lines as a power source, the small bugs in the phones would transmit indefinitely.
These were almost always powered by the local AC line current and so were not particularly portable.
The power is derived from AC lines with battery backup for portable use.
Hansen's right arm shuddered as if he'd grabbed a live AC line.
It may very well be, though, that better clocks are not trusting the AC line.
For longer AC lines, system stability sets the limit to the power that can be transferred.
Each unit from the AC line is decoupled and filtered.
A switcher power supply draws only the power it needs from the AC line.
If someone tried, they could listen to our AC lines and essentially know what was the computer was doing.
It is the AC line, which has a single circuit.