Telepon dan Skema Terkait Interkom

• 1-line telephone status indicator powered from a 3V battery (PDF)
  
• 4-line telephone status indicator that is polarity independent (PDF)
  
• 8-line intercom system using 89C51 microcontroller
  
• 900MHz cordless phone bug
  
• Assorted telephone circuits (ring generator, in-use indicator, audio interface)
  
• Audio Visual Indicator for Telephones
  
• Build your own radio controlled switch from a cordless telephone
  
• Caller ID decoder (requied Postscript file viewer and/or Ordcad schematic capture)
  
• Cellular Phone calling Detector
  
• Cellular Phone calling Detector
  
• Cellular Phone calling Detector
  
• Cellular Phone calling detector (detects RF field)
  
• Cellular Phone Jammer RF Amplifier circuit diagram
  
• Cellular Phone Jammer. Ver 2 circuit diagram
  
• Cordless phone backup power source using LM317L
  
• Cut Phone Line Detector
  
• Cut Phone Line Detector
  
• Cut Phone Line Detector
  
• Cut phone line detector
  
• Cut telephone line detector
  
• Detecting a telephone ring signal
  
• Digisound ring modulator
  
• Digital/Standard Phone Line Tester
  
• DSL / ADSL phone line filter
  
• FM Telephone Bug
  
• FM Telephone Bug
  
• FM Telephone Bug
  
• FM telephone line bug transmitter (88MHz to 94MHz)
  
• GBPPR Cellular Phone Jammer Exciter schematic diagram
  
• Greek telecard reader
  
• GSM-900 Mobile Jammer Book (PDF compressed with WinRAR)
  
• High Power 800 MHz/AMPS Cellular Phone Jammer
  
• High Quality Intercom using LM380 amplifier IC
  
• Hold function for Telephone
  
• Home made PBX / PABX
  
• Homebrew P2JBZ-style cellular / mobile phone jammer circuit
  
• Incoming call indicator (ZIP file)
  
• Isolated Telephone Interface
  
• Isolated Telephone Interface (phone tap) for tape recorder, PC sound card etc
  
• Line in use indicator that handles two independent phone lines (PDF)
  
• Low cost intercom using transistors
  
• Off line Telephone tester
  
• PCS Cellular Phone Jammer circuit schematic
  
• PCS Phone Jammer circuit diagram
  
• Phone "Hold" With Music
  
• Phone Broadcaster / telehone bugging device circuit diagram
  
• Phone Busy Indicator
  
• Phone Busy Indicator
  
• Phone Busy Indicator
  
• Phone call interceptor to stop unsolicited phone calls
  
• Phone In Use Indicator circuit diagram
  
• Phone in-use (manually activated)
  
• Phone In-Use Light
  
• Phone line in use indicator
  
• Phone line indicator
  
• Phone line to audio interface
  
• Phone Off-Hook Indicator using CD4049 hex inverter
  
• 'phone rang' indicator light
  
• Phone to audio interface for SSI202 input
  
• Phone-In-Use indicator
  
• Portable AMPS Cellular Phone Jammer
  
• Portable AMPS Cellular Phone Jammer - Dual Purpose
  
• Portable GSM900 Cellular Phone Jammer
  
• Portable PCS Cellular Phone Jammer circuit schematic
  
• Remote Telephone Bell Ringer
  
• Ringing Phone Light Flasher
  
• Ringing Phone Light Flasher
  
• Ringing Phone Light Flasher using optocoupler and relay
  
• Self-powered phone messenger based on a PIC16C819 microcontroller
  
• Simple alarm with telephone dialler interface
  
• Simple circuit to connect telephone equipment to audio mixer
  
• Simple intercom
  
• Simple Phone Tap
  
• Simple Phone Tap Circuit
  
• Simple Phone Tap circuit diagram
  
• Simple Skype VoIP analog adapter
  
• Simple speakerphone
  
• Simple telephone line tap for intercepting telephone calls
  
• Single-Wire-Telephones for caves and mines
  
• Smart Phone light
  
• Soft Musical Telephone Ringer
  
• Soft musical telephone ringer
  
• Talking phone dial monitor (PDF)
  
• Taxi phone automatic dialler
  
• Telephone amplifier
  
• Telephone amplifier
  
• Telephone auto-dialler (useful for an alarm dialler)
  
• Telephone call screener with voice
  
• Telephone Hold Button
  
• Telephone Hold Button
  
• Telephone Hold Button circuit
  
• Telephone in use light
  
• Telephone Line Filter / Protector
  
• Telephone Line Monitor
  
• Telephone line monitor
  
• Telephone line monitor
  
• Telephone line simulator
  
• Telephone line simulator ideal for testing phone interface projects
  
• Telephone music on hold interface
  
• Telephone privacy adapter
  
• Telephone Record Control using 2N4360, 2N2222 and 2N2102
  
• Telephone Recorder
  
• Telephone Recorder
  
• Telephone recorder to record phone conversations automatically
  
• Telephone ringing circuits
  
• The 89C51 PABX
  
• The Link 4+0 - Internal Intercom (Doesn't offer external line access)
  
• The Link A2B+1 (the Link Telephone Intercom - DTMF version)
  
• The Original 2 Phone Intercom Link Design
  
• Universal telephone hold
  
• Use old telephones as an intercom
  
• Wireless Telephone Bug