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...
- Introduce the principle of FM Telephone Bug
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- Mobile Phone Battery Charger
- Classroom Microphone(LM380 )
- Nokia 7600 cell phone internal
- Nokia 9000, 9000i Communicator cell phones
- Soft Musical Telephone Ringer electronic circuit diagram
- Phone ring circuit schematic
- Telephone Lamp Circuit
- Cellular Phone Calling Detector electronic circuit diagram
- Phone In Use Indicator(2N2222)
- Panasonic G60, X100, X500 cell phone
- Nokia 8910 cell phone internal
- Automatic telephone conversations recording circuit
- BUG wireless telephone circuit
- Computer Microphone (BC413B)
- Wireless Headphone Circuit Diagram
- Ring detect circuit for automatic phone answering
- Traveler Cellphone Battery Charger (NE555)
- Qualcomm Q cell phone
- Soft musical telephone ringer CIRCUIT (1N5819)
- Telephone In Use Indicator Circuit
- Speaker Microphone Circuit
- FM radio Wireless Microphones Circuit
- Wireless am microphone
- 1W stereo Headphone Amp (TDA2822)
- Mobile Phone Portable Charger Circuit Diagram
- Doorphone intercom (LM386)
- Hear with Ultrasound Using Flanagan Neurophone
- How to build Telephone Ringer
- Full-duplex doorphone with 3 wires connection CIRCUIT (TL084
- Mobile Cellphone Battery Charger
- Cardiophone Circuit
- 48V Phantom Feed Supply for Microphones CIRCUIT (OPA277UAE4)
- Soft Musical Telephone Ringer
- Telephone Tapping Indicator
- Wireless headphones transmitter circuit schematic
- Infrared headphones transmitter circuit
- Philips Genie cell phone
- Cassette automatically telephone recording circuit
- Stereo Parabolic Microphone Using 1458
- How Dynamic Microphone Works
- Telephone Ringer(S202T02)
- How to build Phone
- Samsung SPH-I330 cell phone
- Nokia 6800, 6810 cell phones internal
- The Original 2 Phone Link Design
- Automatically Telephone Call Record Circuit
- Nokia 3510, 3510i, 3530, 3590, 3595 cell phones internal
- Balance Input for Microphone Line
- Ring detector telephone ringer circuit
- Nokia 1100, 2300, 2600, N-Gage cell phones internal
- Compressor For Electric Microphone(CA3080)
- HeadBanger Headphone Amp
- Siemens S10 S11 S1088 cell phones
- Telephone Hold Circuit Circuit
- Scramble Encrypted Phone Circuit
- Wireless IR headphone transmitter(2N2222A)
- Hop-On 1800 $10 GSM Cell Phone ??? Would You Mind to Buy One
- How to build 3.6 Volt cell phone battery meter
- How Condenser Microphone Works
- Cut telephone line detector CIRCUIT (LM311N)
- Mobile Phone Call Indicator Circuit Principle
- Headphones with Noise-Canceling Feature
- Cell Phones Charger Schematic Circuit Diagram
- Stereo Mixer for Microphone with 2 Channels
- Cell phone detector aka mobile bug
- Telephone line vigilance principle
- How to build Soft Musical Telephone Ringer
- Sagem 9xx, 3xxx, My-X cell phones
- Panasonic P341i, X11, X70, X80, X88 cell phone
- Clue engaged telephone line
- Dual synchronous telephone toll totalizer circuit
- FM transmitter microphone
- Nokia 3210 cell phone internal
- Mobile Phone Travel Charger (BC548)
- Pulse dialing system for interfacing telephone circuit
- FM Telephone Bug circuit (1N4001)
- The Link Telephone Intercom Every Home Should Have One!
- Speaker Microphone Circuit (BC109C)
- How to build Protection For Telephone Line
- Sony CMD CD5, Z5, Z18 cell phones
- Doorbell Phone ? The Beautiful Combination of Past and Prese
- Nokia Cell Phone circuit diagram
- CMOS RAM poewed repertory dialer phone circuit
- Siemens S40 cell phone
- Telephone line simulator CIRCUIT (BC549)
- Classroom Microphone Circuit
- FM Transmitter Single Transistor Wireless Microphone Circuit
- Nokia 3600, 3650, 3660 cell phone internal
- Phillips Fizz/Spark cell phones
- Dynamic Microphone Preamp
- Phone Busy Indicator electronic circuit diagram
- A Friendly Charger Schematic for Mobile Phones