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...
- Phone line in use indicator CIRCUIT (BF256B)
- Balance Input for Microphone Line
- Cell Phone charger using 1.5V battery
- Spy phone transmitter
- Telephone Guard circuit
- Pantech cell phones
- Microphone preamps circuits using 2N4403
- Ring detect circuit for automatic phone answering
- Mobile Phone Travel Charger Circuit Diagram
- Doorphone Intercom CIRCUIT (LM386)
- Philips SAVY,Fisio 6xx, OZEO, XENIUM, AZALIS cell phones
- Single User JFET Series Telephone Connection
- FM Telephone Bug circuit (1N4001)
- Nokia 8887 cell phone
- Sendo S200 cell phones
- Nokia 6170 cell phone internal
- Reuse Old Mobile Phone Battery
- Telephone call Voice Changer(LM358)
- Siemens SL-10 cell phone
- Solar cell phone charger
- Off-Hook Telephone Line Indicator
- Philips 855 cell phone interface port
- Phone Line Polarity Checker(RJ25)
- How to build Phone Busy Indicator (2N3392)
- XR-T8205 and SL2411 telephone tone ringer circuit
- Cut telephone line detector CIRCUIT (LM311N)
- Doorbell Phone ? The Beautiful Combination of Past and Prese
- Wireless Ir Headphone Transmitter Circuit
- Telephone Party intercom circuit
- Microphone pre amp and Stereophone Drive Circuit Diagram com
- Telephone line for speech voice activity detection
- Siemens S10 S11 S1088 cell phones
- USB Cellphone Charger circuit
- Phillips Fizz/Spark cell phones
- Analog Signal Transmission Over Telephone Lines
- Telephone Bell Simulator Circuit
- TCA3388 telephone line interface circuit
- Sanyo 4500, 4700, 5500, 8100, 8200, 8300, 7400 cell phone
- 3 FM Wireless Microphone Kit
- Telephone Ringer Using Timer ICs(NE556)
- Samsung SPH-I330 cell phone
- 1W stereo Headphone Amp (TDA2822)
- The Universal Cell Phone Chargers Are On The Way to Your Doo
- Creating A Microphone From A Speaker
- Telephone music on hold interface CIRCUIT (BC556)
- How to build FM Telephone Bug
- Samsung S100, S105 cell phones
- BUG wireless telephone circuit
- Nokia 7650 cell phone internal
- Wireless Microphone
- Introduce the principle of wireless telephone problems
- Nokia 8210 Mobile Phone Travel Charger Circuit Diagram
- FM transmitter microphone
- Soft musical telephone ringer (1N4009)
- Dynamic microphone to electret microphone input (BC547B)
- A Friendly Charger Schematic for Mobile Phones(CA3130)
- Cellular Phone Calling Detector Circuit (1N5819)
- FM Telephone Bug
- Panasonic G50, G51, G70, A100, A101, A102, X300 cell phones
- Panasonic GD55 cell phone
- How to build Cellular Phone Calling Detector Circuit Schemat
- Dynamic microphone to electret microphone input
- Door Phone
- Cut Phone Line Detector electronic circuit diagram
- Low Noise Balanced Microphone Preamp (2N4403)
- Infrared headphones receiver circuit
- Nokia 6260 cell phone internal
- Samsung SCH-A2000, SCH-A7500, SCH-A7600 cell phones
- Cellular phone detector circuit schematic
- HowTo: Make a LoFi Mic from an Old Telephone
- How to build A Friendly Charger Schematic for Mobile Phones
- USB Ultrasound Imaging Became Possible with Smartphone!
- FM Telephone Bug CIRCUIT (BC107)
- FM Transmitter Single Transistor Wireless Microphone Circuit
- Cellphone Calling Detector Circuit Diagram (1N5819)
- Classroom Microphone(LM380 )
- Hop-On 1800 $10 GSM Cell Phone ??? Would You Mind to Buy One
- How to build PIC Security System Dials Your Cell Phone
- The Link Telephone Intercom Every Home Should Have One!
- Underwater microphone (T8A820M)
- Wireless headphones transmitter circuit schematic
- Long range directional microphones-myth and reality
- Phone ringtones 556 pairs timer principle explanation
- Telephone in use indicator.
- Siemens C30, M30 cell phones
- Nokia 1100, 2300, 2600, N-Gage cell phones internal
- How to build Mobile Phone Travel Charger Circuit Diagram
- Wireless Fm Microphone
- Panasonic G60, X100, X500 cell phone
- NPN photodevice electronic phone bell circuit
- BiPAC 6404V(G)P Datasheet for Your Cheap Telephone Calls
- Nokia 8800 cell phone internal
- Siemens ST55 cell phone
- Two Identical Telephone Intercom Circuit
- Fet Microphone Mixer Circuit
- Spy for Two Telephone Lines
- Dynamic Microphone Preamp
- FM Wireless Microphone circuit
- Cellular Phone calling Detector
- Telephone Hold Circuit Circuit