Telephone Hold Button

Although a hold feature is standard on most new phones, a lot of us still use the origional bell phones. Those of us that require a hold feature will find this circuit very useful. It is easy to build, and is compact enough to be installed inside the phone with no real problem. It is also powered by the phone line itself, eliminating the need for batteries.

Schematic

Parts

Part Total Qty. Description Substitutions R1 1 1.5K 1/4 W Resistor R2 1 1K 1/4W Resistor D1 1 1N4002 Silicon Diode 1N4003, 1N4004, 1N4005, 1N4006, 1N4007 SCR1 1 C106Y SCR LED1 1 Red LED Green LED, Yellow LED S1 1 Normally Open Push-Button Switch MISC 1 Wire, Board, Case (If Used)

Notes

1. To place a call on hold, simply hold down the button while hanging up the phone. To take a call off hold, just pick up the phone, or any extension.
2. Even though this is a simple circuit, you may have to check with your phone company before use.