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Hello box

Greet visitors on the phone and let them leave messages.

hello box image 1
There are two parts; the hello box and the inside box. The hello box is a battery powered annunciator box with a push button and microphone, generally attached near a front door of a home. The inside box has a socket for power from a plug in transformer and two phone sockets, in and out.

A visitor who pushes the button on the hello box hears a "ding dong" sound and the telephone plugged into the inside box rings. The resident can then pick it up and talk to the visitor.

If a resident is far from the front door, busy, or in bed it is more convenient to pick up a telephone than go to the front door. In a walk up business a merchant in the back could greet the customer through the hello box before coming to the front.

Connect an answering machine and visitors can leave messages at a home or business. Visitors can also be screened by hearing them before responding.

The inside box can be plugged into the phone line as it enters the house so all phones ring when the button is pressed. If no incoming line is connected to the inside box the outgoing line is a dedicated intercom.


Volume & sensitivity (adjust when installing)
Adjust these like the controls on speaker phones.
Ring count (adjust when installing)
This controls the number of rings when the button is pressed.
Button (optional)
Connect a switch, like a floor mat or door switch. Closing the switch is like pressing the button.
120 volts, 24 volts (optional)
Connecting a power supply will conserve batteries.
Antenna (optional)
Adding an antenna will increase range.
Batteries (insert when installing)
Batteries last a long time because the hello box only draws power during conversations and most of them will be short.
Technical notes:
When no ring signal is received the inside box has no effect on the phone connected through it. When a ring signal is received by the inside box it determines if the phone is already off the hook. If so it injects an incoming call sound. The resident can then end their conversation and briefly hang up to open the line to the front door. Alternatly the resident can ignore the ring. If the phone is on the hook the inside box opens the line so incoming calls will hear a busy signal and then injects a ring signal.

The hello box draws no power in a resting state. When the button is pushed it makes a "ding dong" sound and transmits a ring count to the inside box. Then it waits for the connection to open. If the connection has not opened when the rings are finished it returns to a resting state. After a connection closes it also returns to a resting state. Since most conversations will be short the battery life will be long.

The parts are mostly off the shelf and manufacturing would consist mostly of assembly. Two control chips will have to be programmed.

hello box image 2

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