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To: Morgana

Say the female victims of breast cancer that carry their smart phones in their bra. It’s a 3 watt radio transceiver for crying out loud.


3 posted on 02/13/2025 12:21:08 PM PST by blackdog ((Z28.310) Be careful what you say. Your refrigerator may be listening & reporting you.)
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To: blackdog

Say the female victims of breast cancer that carry their smart phones in their bra. It’s a 3 watt radio transceiver for crying out loud.

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Um - It depends....

PCS phones are low power due to baseband spread-spectrum (CDMA - code-division multiple access). Each phone within a cell tower range has a different spreading code so multiple phones can talk at the same time.

Side trip - CDMA carried out to lotsa high-speed bits is military encryption stuff.

GSM phones use TDMA (time-division multiple access). Each phone within a cell tower range has frequency within a set of frequencies, each frequency has eight time slots. A phone will transmit a burst when its time slot comes around.

Max is 1 watt, stated in several references I checked. Typical power is somewhat less, 125 milliwats or lower.

The PCS system transmitter is power-controlled so the closer you are to the tower the less power it transmits.

The GSM phone will transmit its burst at full power. That’s why you occasionally hear it in audio systems. However, it has one time slot in eight so average power is again 125 milliwatts.

The old FM cellphones (bricks) could go to three watts if I remember right (but I’m an Old Fart).


4 posted on 02/13/2025 1:17:38 PM PST by dagunk (-- Unknown)
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