Analog phones

Phone Circuits

• Phrack
• Telephone circuits/projects
• Inside the Phone Wiring - explains how phones are wired internally — applies mostly to older analog phones.
• Telephone circuits and projects
• Telephone Projects with circuit diagrams
• Bowden's Telephone project circuits
• Techlib Telephone circuits
• Tomi Engdahl designed Telephone Circuits with detailed explanations
• Discover Circuits - Telephone Excellent list of URLs to telephone related circuits.
• Directory of links to telephone circuits
• PSTN and POTS fundamentals Training, video/DVD courses, free online tutorials on telephony, digitization, related topics

Door Phones

Rotary Dial to DTMF converters

• See "PULSE TO TONE CONVERTER" at: http://www.sandman.com/digit.html

Phone Tools and Equipment

• http://www.yeastar.com/ - Provide up to 16 ports Skype Exchange for normal PBX, Skype on office phone
• http://www.sandman.com/ - Telecom tools and door phones, and more
• http://www.jechtech.com/ - Telephone line simulators
• http://www.safetalks.net/ - Telephone scramblers
• Voicent Communications - Voice modem based smart autodialer, predictive dialer, and VoiceXML gateway. See Autodialer from Voicent, Predictive dialer from Voicent, and VoiceXML gateway from Voicent
• Database Systems Corp. analog phone systems including voice broadcast and IVR features
• CARE analog phone systems - Telephone reassurance calling program using RUOK analog autodialer phone systems with voice broadcasting.

History

• Telephone Tribute extensive collection of historical and technical information on the telephone industry

Information

• epanorama Great collection of information on PSTN technology