This simple circuit can indicate a misuse or tapping of Telephone line through a loud alarm. The circuit is too simple and can be easily assembled on a...
An op-amp IC (741) amplifies the audio signal from MIC1, and R12 controls its gain. Audio is fed to the oscillator circuit Q1 and related components. D...
pinout 9 pin Nokia 7600 cellphone specialconnector at the mobile phone Pin Signal Description 3,7 Gnd 4 MBUS 5 Vpp 8 F-Bus Rx 9 F-Bus Tx A Vbat B BSI C...
This article describes the FM telephone line bug transmitter CIRCUIT (BC109). The content is very simple, very helpful. Components in this article can ...
Figure 1 The circuit is designed to connect in parallel with the telephone line, to monitor and detect if any telephone in the same line is busy, with ...
full pinout 5 pin Nokia semi-round cellphone specialconnector at the cellular phone Pin Signal Description 1 GND 2 MBUS 3 Vpp 4 Rx 5 Tx For Nokia 3220,...
Have you ever been using the modem or fax and someone else picks up the phone, breaking the connection? Well, this simple circuit should put an end to ...
Figure 1 The project produces noise-canceling headphones which allow the background noise to be minimized while listening to music. To keep the microph...
Radio Circuits Using this electronic schematic , can be designed a very simple cellular phone detector circuit which can sense the presence of an activ...
10 pin cellphone specialconnector at the mobile phone Pin Signal Description 8 Tx 9 Rx 10 GND Source:www.pinouts.ru Reprinted Url Of This Article: http...
This article describes the Telephone line simulator CIRCUIT (BC549). The content is very simple, very helpful. Components in this article can help you ...
This Microphone Preamp circuit shows that it is possible to use the speaker as a microphone, and is specifically designed to beginners because of its s...
This article describes the Circuit Diagram of Cordless Phone Battery Backup (LM317L). The principle is very simple, very practical. The circuit compone...
for data/flash cable only 5 pin cellphone specialconnector at the cellular phone (keypad up) Pin Signal Description 2 GND 4 Tx 5 Rx Source:www.pinouts....
This article describes the Phone Busy Indicator (BC148). The content is very simple, very helpful. Components in this article can help you understand b...
LM 386 is just right for a door phone application. It is very useful application in the present urban households. One condenser microphone and a speake...
Prosthetic Arm with Smartphone Trevor Prideaux, a fifty year old man from United Kingdom was born without his left forearm. Years later he was given a ...
for data/flash cable only 7 pin Panasonic cellphone specialconnector at the cellular phone Pin Signal Description 3 Rx 4 Tx 5 GND 5,6,7 batt pins Sourc...
A while ago I got an email asking for the schematic of a circuit to detect cut phone lines. It didn't take me long to find this circuit in Electronics ...
Use this infrared headphones receiver with the ir headphones transmitter. Use 600Ω headphones. BPW41N and BP104 have a filter for visible light and ar...
Mic mixer circuit Welcome back to Free circuit dot com again,today we have still audio circuit for your build . The circuit is a basic 3 input mic mixe...
The MC34017Tone Ringer derives its power supply by rectifying the ac ringing signal. It uses this power to activate a tone generator and drive a piezoc...
for data/flash cable only 16 pin Sharp GX10 cellphone specialconnector at the cellular phone (keypad up) Pin Signal Description 1,9,14 GND 2 link to 10...
This article describes the Phone ring circuit schematic (BC848). The content is very simple, very helpful. Components in this article can help you unde...
This article describes FM Wireless Microphone (MAX4467). The principle is very simple, very practical. The circuit components can help you understand b...
ThisFM spy telephone circuitis mounted serrial with the phone line. When is signal on the wires thistransmitterwill radiate airwaves thru the wires wic...
This article describes the Doorphone intercom (LM386). The content is very simple, very helpful. Components in this article can help you understand bet...
for data/flash cable only 5 pin cellphone specialconnector at the mobile phone (batt pins are up) Pin Signal Description 1 Gnd 2 Rx 3 MBUS 4 Tx 5 Vpp S...
for data/flash cable only 23 pin Samsung S100 cellphone specialconnector at the cellular phone Pin Signal Description 16 Data out 15 Data in 18,20,22 G...
Do you worry that charging the mobile phone when you want to travel,Mobile Phone Travel Charger can help you. This is an cell phone travel charger util...
- Remote telephone line extension bell ringer circuit
- Mobile Phone Travel Charger
- Full-duplex doorphone with 3 wires connection CIRCUIT (TL084
- How to build Protection For Telephone Line
- PA System Phone Pager Circuit
- How to build Telephone Ringer
- Circuit Diagram of Cordless Phone Battery Backup(LM317L)
- Automatic telephone conversations recording circuit
- Classroom Microphone Circuit
- A JFET-MOSFET Headphone Driver
- Wireless infrared headphones receiver principle
- Boundary Layer Dish Microphone (MAX232)
- Sendo S200 cell phones
- Telephone Spy Conversation Recording Circuit
- Wireless Ir Headphone Receiver Circuit
- Computer Microphone (BC413B)
- Watch-Dog For Telephones(NE555)
- BiPAC 6404V(G)P Datasheet for Your Cheap Telephone Calls
- Nokia 3210 cell phone internal
- Mobile Phone Call Indicator Circuit Principle
- FM telephone bug.
- Mobile Phone Battery Charger(LM7806)
- Not Just Another Headphone Amp
- Protection For Telephone Line(V250LA4)
- Cell Phone charger using 1.5V battery
- Telephone music on hold interface (LH0032)
- Sharp GX1, GX10, GX10i, GX20, GX21, GX22 cell phones
- Multi Purpose Telephone Circuit Diagram (BC108)
- How Dynamic Microphone Works
- A Friendly Charger Schematic for Mobile Phones(CA3130)
- Samsung z105 cell phone
- Telephone line simulator CIRCUIT (BC549)
- Panasonic GD55 cell phone
- The Link A2B 1 (the Link Telephone Intercom - DTMF version)
- Analog Signal Transmission Over Telephone Lines (TC9400)
- A Smartphone Dock Built Inside Man
- Sagem My-C2 cell phones
- 48V Phantom Feed Supply for Microphones CIRCUIT (OPA277UAE4)
- Telephone In-Use Indicator(BS108)
- PCD3360 integrated multitone telephone ringer
- Philips 855 cell phone interface port
- Soft Musical Telephone Ringer Circuit
- Mobile Phone Travel Charger (BC548)
- FM transmitter microphone
- Mobile Phone MP3 Charger Circuit Diagram
- How to build 3.6 Volt cell phone battery meter
- Cut telephone line detector CIRCUIT (LM311N)
- Introduce the principle of FM Telephone Bug
- How to build FM Telephone Bug
- Cordless Phone Backup principle
- Sanyo 4500, 4700, 5500, 8100, 8200, 8300, 7400 cell phone
- Doorbell Phone ? The Beautiful Combination of Past and Prese
- Samsung E720, E810, P730 cell phones interface port
- Low Noise Balance Microphone Pre-Amp using a TL071
- Telephone Hold Button electronic circuit diagram
- Siemens S40 cell phone
- Nokia 6100, 6108 cell phone internal
- Telephone Line Engaged Indication
- Cell Phone Jammer Circuit Diagram
- Door Phone Intercom (LM386)
- High Performance MEM Microphone (ADMP441)
- Telephone call Voice Changer(LM358)
- How to build Soft Musical Telephone Ringer
- FM Telephone Bug(2SA933)
- Dynamic Microphone Preamp
- Philips SAVY,Fisio 6xx, OZEO, XENIUM, AZALIS cell phones
- Nokia 2110 cell phone
- Apple Mobile Phone Circuit Diagram (M42C)
- NEC N21, N22, N223i cell phone
- Mobile Cellphone Battery Charger Circuit Using 555
- Nokia 16xx, 3110, 8110 cell phones
- Nokia 6500, 6510, 8310 cell phones internal
- Phone ringtones 556 pairs timer principle explanation
- Telephone Recorder
- Nokia 1100, 2300, 2600, N-Gage cell phones internal
- Phone Broadcast circuit
- Fet Microphone Mixer Circuit
- Sagem 6xx, 7xx, 8xx cell phones
- Panasonic GD30, GD50, GD70, GD90 cell phones
- Motorola MC34118 Speakerphone Adapter Circuit
- Nokia Cell Phone circuit diagram
- Telephone ringing circuits
- Speaker Microphone Circuit (BC109C)
- Easy Loudspeaker Circuit For Telephone(BC548 )
- Wireless headphones receiver circuit schematic
- Telephone Hold Button
- Wireless Microphone FM Transmitter
- 1W stereo Headphone Amp (TDA2822)
- Phone Line Polarity Checker(RJ25)
- Preamp for Speaker as a Microphone
- Dynamic Microphone Preamp Mono by Transister C945 (with PCB)
- Nokia 2650 cell phone internal
- Telephone Party intercom circuit
- Cellular Phone calling Detector CIRCUIT (D438)
- Remote Telephone Ringer
- Panasonic P341i, X11, X70, X80, X88 cell phone
- Classroom Microphone(LM380 )
- Telephone in use indicator.