A timer-controlled doorbell device has been developed using two 555 timer ICs in monostable mode, combined with a relay ...

The Battery Doorbell Pro uses the same black and satin nickel enclosure as the Battery Doorbell Plus ($179.99), and at 5.1 by 2.4 by 1.1 inches (HWD), it shares the same dimensions.

Ring’s Wired Doorbell Pro offers lots of bells and whistles to justify its price, including highly detailed video, 3D motion detection, and a unique aerial view of motion activity.

Ring’s Battery Doorbell lacks many of the features that you get with its more expensive sibling, the $229.99 Battery Doorbell Pro, but at $99.99, it's much more affordable and just as easy to ...

The latest addition to Ring’s growing stable of video doorbells, the Battery Doorbell Plus ($149.99), is the company's most advanced battery-powered model yet.

To access the doorbell settings, tap the gear button in the top right corner. In this screen you can enable/disable ring and motion alerts, configure motion and video settings, enable push alerts ...