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A 555 -Timer Based Motorcycle Alarm

This circuit features an intermittent siren output and automatic reset. It can be operated manually using a key-switch or a hidden switch; but it can also be wired to set itself automatically when you turn-off the ignition. By adding external relays you can immobilize the bike, flash the lights etc.... [read more]

IR Remote Control Jammer

Don't like your little brother's TV channel selection? Hate the volume your wife sets the stereo at? Want to just annoy someone? This circuit does all that and more by jamming most IR remote signals. The circuit releases a flood of pulsing IR light that confuses the reciever by corrupting the data stream.... [read more]

Applications with Voltage Regulator L200

Here they exist two regulator circuits, that use the IC L200, as regulator of voltage and current, the company SGS-Thomson, which give these circuits. In circuit Fig.1, we can regulate the output voltage, with the RV1, while in the Fig.2, we can regulate also output voltage – current, with the TR2 and TR1, respectively. More information on characteristics for L200, you can see in list datasheets. Shortly will be added also certain other useful circuits with L200.... [read more]

Knightrider lights for model cars

This simple circuit drives 6 LEDs in 'Knightrider scanner mode'. Power consumption depends mainly on the type of LEDs used if you use a 7555 (555 CMOS version).... [read more]

Ultra-High Fidelity High Power Amplifier Reference Design

The LME49830 EF125WT1 amplifier PCB module showcases National Semiconductor’s LME ultra-high fidelity power amplifier input stage ICs (drivers). The LME49830 is a fully complementary bipolar 200V input stage IC with 56mA (typical) of output current that has been optimized for audio applications. With 56mA of current drive, the IC can drive numerous power transistors to achieve high levels of output power. The LME49830’s ultra-low distortion and low-noise, combined with a user adjustable compensation scheme results in a tightly controlled, but highly dynamic listening experience.... [read more]

A Transistor Based Motorcycle Alarm

This circuit features a timed output and automatic reset. It can be operated manually using a key-switch or a hidden switch. By adding an external relay, it will set itself automatically - and/or immobilize the machine - every time you turn-off the ignition. It's easily adapted for a 6-volt system - so it will protect your "Classic Bike".... [read more]