Cellphone rings inside microwave oven

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A cellphone rings inside a microwave oven because cellphone frequencies, which operate at 900/1800 MHz in Europe and 950/1900 MHz in the US, can penetrate the microwave's Faraday cage. Microwaves typically operate around 2.4 GHz, a frequency chosen for its effectiveness in heating food and lack of prior communication systems. While the microwave blocks some signals, cellphones are adept at detecting weak signals, allowing them to ring even inside the oven. However, the phone may not be able to transmit or receive voice calls effectively while inside. This phenomenon highlights the limitations of microwave shielding against certain radio frequencies.
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Why a cellphone rings inside microwave oven? Does the microwave oven don't block cellphone radiation?
 
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cellphone frequencies are much higher than microwave frequencies hence they penetrate through the faraday cage in the microwave. hell I've seen cell phone calls go through a lab faraday cage.
 
Actaully they are lower.
Most oven operate around 2.4Ghz. (Not only is this convenient for water molecules in food but because there weren't any communications systems at this frequency.
Unfortunately because there weren't any exisitng communications standards using this - it was also chosen for bluetooth and Wifi.)

GSM phones operate at 900/1800 Mhz in Europe or 950/1900 in the US.
The reason your phone rings is that it is very good at picking up extremely weak signals, at least to be able to detect a call. It might not be able to transmit/recv voice while in the oven - try getting inside the oven and answering it.
 
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