There is no room card in my apartment. I can get in by other means.

There is no room card in the apartment. You can get in by other means. Ask the front desk to re-open a room card to open the door. Return the room card when you find it. Just say you forgot your room card. You can ask the front desk to reissue it and then return two room cards. If you lose your previous room card, the hotel will deduct the cost of the room card, probably around 50 yuan.

The room card itself has a cost, and it also reminds tenants to protect the room card, so a high loss reporting fee will be set for the lost room card. So, I forgot my room card, so I asked the front desk to reissue it.

Function of apartment card

The room card can control the lights and sockets in the room without plugging in the slot. All the lights and sockets in the room don't work, so the room card is equivalent to a switch on the road.

When the light plug of the disconnector is plugged into the socket, all other lights in the room go out.

The room card of an apartment or hotel has a high safety factor and is more convenient to use. The basic principle of the room card is that the RF reader emits a set of electromagnetic waves with a fixed frequency to the room card, and there is an LC series resonant circuit in the card, the frequency of which is the same as that emitted by the reader. In this way, under the excitation of electromagnetic waves, the LC resonant circuit produces * * * vibration, which charges the capacitor.

At the other end of the capacitor, an electronic pump with unidirectional conduction is connected to send the charge in the capacitor to another capacitor for storage. When the accumulated charge reaches 2V, this capacitor can be used as a power supply to provide working voltage for other circuits, and transmit data in the card or receive data from the card reader.