Telephone and intercom related schematics (89)

 

• Cellular Phone (4)
• Standard Telephone (72)
• Intercom (13)

 

 

 

 

 

 

Cellular Phone

1. Cables, Interfaces and Pin-Outs
2. Nokia 6190 Data Cable
3. Nokia l Pinouts & Schematic Cable
4. Mobile Phone Battery Charger (PDF)

 

 

Standard Telephone

1. 9-Line Telephone Sharer (PDF)
2. Audio Visual Ringer
3. Connect line-level signal to phono input
4. Contactless Ringer for Telephones (PDF)
5. Cordless Phone Backup
6. Cut Phone Line Detector
7. Digital/Standard Phone Line Tester
8. Detecting a telephone RING
9. Dodatno telefonsko zvono
10. DTMF Generator/Decoder
11. Dva telefona na jednoj liniji
12. FM Telephone Bug
13. Hands-Free Telephone
14. How to record telephone conversations
15. Infinity Transmitter
16. Indikator zauzetosti telefonske linije
17. Interni telefonski sistem
18. Low-Cost PCO Billing Meter
19. Multipurpose Circuit For Telephones
20. Music-On-Hold Box
21. Music On Hold for Thelephones (PDF)
22. Off line Telephone tester
23. Ozvučenje telefonske linije
24. Parallel Telephones with Secrecy
25. Phone Broadcaster
26. Phone Busy Indicator
27. Phone In Use indicator
28. Phone In-Use Light
29. Phone Line 1 Status (PDF)
30. Phone Line 2 Status (PDF)
31. Phone Line 4 Status (PDF)
32. Phone Line Status Light (PDF)
33. Phone Off-Hook Indicator
34. 'Phone rang' indicator light
35. Phone Ring Timer
36. Phone Recorder
37. Phone to audio interface (SSI202 input)
38. Ringing Phone Light Flasher
39. Serijski komunikacioni sistem
40. Simple Phone Tap
41. Simple ring modulator
42. Simple Telephone Ring Tone Generator (PDF)
43. Simple telephone test circuit
44. Smart Phone light
45. Snimanje telefonskog razgovora
46. Svetlo za telefon
47. Talking Phone Dial Monitor (PDF)
48. Suction Cup Phone Pickup (PDF)
49. TELEPHONE AUTO RECORD
50. Telephone Blinker
51. Telephone Bug
52. Telephone Call Meter Using Calculator And COB
53. Telephone Controlled Night Light
54. Telephone Conversation Recorder
55. Telephone Headgear
56. TELEPHONE HOLD BUTTON
57. Telephone in use light
58. Telephone Line Based Audio Muting and Light-On Circuit
59. Telephone Line Simulator
60. Telephone line surge protection
61. Telephone Line Vigilant
62. Telephone Number Display
63. Telephone privacy adapter
64. Telephone Recorder
65. Telephone Recording Circuit
66. Telephone ringing circuits
67. Telephone Ringer using Timer ICs
68. Telephone Switch for Tape Recorder (PDF)
69. Telephone Tap
70. Telephone Transmitter (PDF)
71. Universal Telephone Hold (PDF)
72. Wireless Telephone Eavesdropper

 

 

 

Intercom

1. 2-Line Intercom-Cum-Telephone Line Changeover Circuit
2. Full-duplex doorphone with 3 wires connection
3. Govorom aktivirani intercom
4. High Quality Intercom
5. Intercom - Two Way
6. Intercom
7. Interfon
8. Low-cost Transistorised Intercom
9. Practical Intercom
10. Simple Intercom
11. Telephone Intercom
12. Two Station Intercom (PDF)
13. Use old phones as an intercom