Line monitor schematics

Detect line interference with this innovative circuit and safeguard your telephone communication. This 2N2222A oscillator circuit provides real-time alerts of open lines, shorts, and unauthorized connections, ensuring your privacy and peace of mind.... [read more]

Build your own telephone recorder and capture every conversation with this ingenious circuit. This 270K resistor based design automatically records calls when the phone line voltage drops to 5 volts, offering a powerful way to preserve important discussions.... [read more]

Build a simple phone line monitoring circuit and safeguard your connections from unwanted interruptions. This innovative design, utilizing a red and green LED, instantly alerts you when a phone line is in use, ensuring uninterrupted communication. Easily integrated inside your phone, this circuit offers a powerful solution for protecting your calls and sparking your inventive projects.... [read more]