- Detecting a telephone RING 1
- Detecting a telephone RING 2
- Detecting a telephone RING 3
- Detecting a telephone RING 4
- Digital/Standard Phone Line Tester
- Hands-Free Telephone
- Hold function for Telephone
- Isolated Telephone Interface
- Music-On-Hold Box
- Phone in use indicator 1
- Phone in use indicator 2
- Phone in use indicator 3
- Phone in use indicator 4
- Phone in use indicator 5
- Phone in use indicator 6
- Phone in use indicator 7
- Phone Line to Audio
- Phone rang indicator light
- Phone Recorder
- Phone to audio interface (SSI202 input)
- Telephone Controlled Night Light
- Telephone Line Monitor (Plans)
- Telephone Power
- Telephone Tap
- Use old phones as an intercom
- Wireless Telephone Eavesdropper
Telephone
telephone-related electronic circuits
