Doorphone Intercom
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Doorphone Intercom
Four types of modern doorbell
Modern doorbell can be divided into wired doorbell , wireless doorbell (Remote Control doorbell), intercom doorbell, video door phone
There are two types of Wired doorbell:DC and AC power.
DC supply power by battery, 220V power supply is used by AC. DC doorbell structure is simple, using IC block, and lower cost. AC doorbell is the principle of making use of power coil.
Remote control doorbell has two sub-DC and AC.
The remote control of DC switch on dry batteries, dry batteries in the doorbell is also used. Communication with the remote control switch on the battery while the doorbell AC power supply, the principle of just more than wired doorbell one more launcher, and a receiver. Wired doorbell has the advantage of stable and reliable, defects which had to wait a good line, wireless doorbell without row of the advantage of cable can be use; Disadvantages: have distance limitations vulnerable to interference.
Generation doorbell, intercom, video doorbell.
Doorbell intercom doorbell in the original function, add the intercom, it points to the indoor unit and outdoor unit. Indoor unit looks like a telephone, listen to tell. Outdoor unit is a control panel on a doorbell and intercom button holes for indoor and outdoor dialogue.
The wireless video door phone is developed based on intercom doorbell. The most advanced doorbell intercom system, based on its intercom, increase in the indoor unit display an increase in outdoor camera, so to those who looks at a glance, the function adds an automatic unlock button, convenient and to match the electronic door locks.
For more information please refer to:
http://www.espow.com/wholesale-4-tft-lcd-wireless-video-doorphone.html
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