Sajee tronics

For secure communication among sensors, secret keys must be established between them. Many key establishment techniques have been designed to address the trade-off between limited memory and security, but which scheme is the most effective is still debatable Sunil Gupta & Mriutnjay Singh Security allows wireless sensor networks (WSNs) to be used with confidence. Without security, the use of WSN in any application domain would result in undesirable consequences. The basic idea of a WSN is to disperse tiny sensing devices that are capable of sensing some changes of incidents/parameters and communicating with other devices, over a specific geographic area for some specific purposes like target tracking, surveillance and environmental monitoring. Basically, the major challenge for employing any efficient security scheme in wireless sensor networks is created by the size of sensors, followed by the processing power, memory and type of tasks expected from the sensors. Challenges

For the Broad Band to work properly, you are requested to use a splitter from each and every rosette from where a telephone, FAX or any other instrument is connected to the Telephone Line on which Broad Band connection / provision is given. The telephone line extended from the exchange to the your  premises is terminated at the rosette. Up to this point,  Data and Voice signals  traverse on  single line  and as it enters the splitter  (LINE JACK) , the signals are split and  voice signals  get out of the splitter via  PHONE JACK  of the splitter and Data signals  get out of the splitter via  MODEM JACK  of the splitter. Wherever a telephone instrument is used without a splitter on a broadband line, you  may experience disconnection of internet connectivity whenever an incoming call is received on the telephone. PLEASE NOTE:  No telephone extension cabling is to be used to connect the modem to the splitter, as this was not designed to carry a broadband signal. If

Here is a simple low-power inverter that converts 12V DC into 230-250V AC. It can be used to power very light loads like window chargers and night lamps, or simply give shock to keep the intruders away. The circuit is built around just two ICs, namely, IC CD4047 and IC ULN2004. IC CD4047 (IC1) is a monostable/astable multivibrator. It is wired in astable mode and produces symmetrical pulses of 50 to 400 Hz, which are given to IC2 via resistors R1 and R2. IC ULN2004 (IC2) is a popular 7-channel Darlington array IC. Here, the three Darlington stages are paralleled to amplify the frequencies received from IC1. The output of IC2 is fed to transformer X1 via resistors R3 and R4. Transformer X1 (9V-0-9V, 500mA secondary) is an ordinary step-down transformer that is used here for the reverse function, i.e., step up. That means it produces a high voltage. Resistors R3 and R4 are used to limit the output current from the ULN to safe values. The 230-250V AC output is available across the hig

This circuit counts mains supply interruptions (up to 9) and shows the number on a 7-segment display. It is highly useful for automobile battery chargers. Based on the number of mains interruptions, the user can extend the charging time for lead-acid batteries. Fig. 1: Circuit of mains interruption counter with indicator Fig. 1 shows the circuit of the interruption counter with indicator. A 9V (PP3 or 6F22) battery powers the entire circuit. Fig. 2 shows the block diagram of the mains interruption counter circuit along with the battery charger and lead-acid battery as used in automobile battery charger shops. When 9V is applied to the circuit, IC2 is reset by the power-on-reset signal provided by capacitor C3 and resistor R5 and the 7-segment display (DIS1) shows ‘0.’ The 230V AC mains is fed to mains-voltage detection optocoupler IC MCT2E (IC1) via capacitor C1 and resistors R1 and R2 followed by bridge rectifier BR1, smoothing capacitor C2 and current-limiting resistor R2. Il

Price: US $118.00 In clear range, this transmitter can broadcast about 40meters! This auction includes 0.05watt TV  Transmitter PCB , antenna  and  power supply . *With a good antenna theTV transmitter will broadcast better. The transmission range depends on many factors. The true distance is based on the sensitivity of the receiver, antenna of the receiver, building and other obstructions which are between the transmitter and receiver. The distance will much more in open countryside. Specifications: Frequency range: 46MHz ~ 920 MHz Tuning Step:0.25M Hz   Transmit Power:  0.05   watts The MC44BS373CA audio and video modulator is for use in VCRs, set-top boxes, and similar devices. • Supports multiple standards • TV output level 82 dBμV typical • 5- and 3.3-V compatible I2C bus

You can use your dish antenna and UHF/VHF in a same line. You have only one antenna socket in your wall ?? How to connect Your UHF.VHF + Dish antenna in a same wire ?? SATELLITE / TV DIPLEXER Provides low loss diplexing of DBS and TV signals. Separates TV and DBS signals prior to satellite receiver input, and filters harmonics in the off-air spectrum from satellite conversion devices. The DPD2 diplexer is specifically designed for Dish Networks TM DP44 installations, allowing 2 amp passing without burning out. Wiring diagram