Simple Op Amp Radio

This is basically a crystal radio with an audio amplifier which is fairly sensitive and receives several strong stations in the Los Angeles area with a minimal 15 foot antenna. Longer antennas will provide a stronger signal but the selectivity will be worse and strong stations may...

Infrared Remote Control

This circuit will allow you to turn on any piece of equipment that operates on 115 volts ac. The receiver circuit is based on the Radio Shack infrared receiver module (MOD), part number 276-137. It is also available from some of the other sources listed on my Links page. The MOD...

Garage Stop Light

A novel use of solar cells makes positioning your car in the garage rather easier than old tyres, a mirror, or a chalk mark. The six solar cells in figure 1 serve as power supply and as proximity sensor. They are commercially available at relative low cost. The voltage developed...

Small Power Amplifier 8W 8Ω with TDA 2030

Although the TDA2030 can deliver 20 watts of output power, I deliberately reduced the output power to about 8 watts to supply 10 watt speakers. Input sensitivity is 200mV. Higher input levels naturally will give greater output, but no distortion should be heard. the gain is set by...

The worker can simply press the pagedown button of cell phone jammer

The worker can simply press the pagedown button of cell phone jammer . Promise as a wireless presenter products use 2.4G ISM band. The bands product, if less than 1 mW transmit power, is not obtained "Radio Transmission Equipment Type Approval Certificate (SRRC)" The. ISM band that is industrial, scientific...

Electronic Security System

This reliable and easy-to-operate electronic security system can be used in banks, factories, commercial establishments, houses, etc. The system comprises a monitoring system and several sensing zones. Each sensing zone is provided with a closed-loop switch known as sense switch....