Telephone electronic circuits list :
- Telephone Ringer using 556 dual timers
- Two line intercom plus a telephone changeover switch
- Telephone line based audio muting and light on circuit
- Having secrecy in parallel telephones
- Telephone call meter using calculator & COB
- Phone Broadcaster
- Conversation Recorder
- Multipurpose Circuit for telephone
- Remote control using telephone
- Cordless phone backup
- Telephone Number Display
- Smart Phone light
- Telephone Headgear
- Telephone Line Vigilant
- Audio Visual Ringer
- Off line Telephone tester
- The Link Telephone Intercom ? Every Home Should Have One!