The core of this construction is 16-Bit Stereo Digital-To-Analog Convertor with USB interface PCM2702. PCM2702 needs only few additional parts to work. The schematic is not complex. Sound card can be powered directly from USB port (jumper W1) or from external power supply (jumper W3). PCM2702 needs two power supply 3.3V (3V-3.6V) and 5V (4.5V-5.5V). I used fixed output voltage LDO TPS76733Q for 3.3V (IO2) and adjustable output voltage LDO TPS76701Q for 5V (IO3). Both LDO.....
This circuit was formed to create a wireless alarm from a normal magnetic contact. By fixing the magnet to the leaf of a door, or swing of a drawer, it is easy to reveal the opening. To transmit the signal to a control anti-theft we modify the circuit of a remote control to activate it only for as long as necessary . Without the change, leaving the door open for the batteries would run out in a few hours! This transmitter is powered by a battery of 9 volts for a period of.....
Schematic and parts list needed to construct a simple Light Alarm. Use this to protect your medicine cabinet, cash drawer or any cabinet...
Soundblaster soundcard series (SB16, SB32, AWE32 and AWE64) have all a microphone input designed to be used with the electret microphones which come with the soundcard package (some packages) or with separate microphone designed to be used with SoundBlaster soundcards (there are separate microphones and some monitors have built-in microphones like this). Because the microphone input needs very high input levels it is not suitable to be used with any other micophone type.....
The amplifier shown here was previously incorrectly referred to as `El-Cheapo`. Thanks to a reader who had a copy of the original 1964 article, it was immediately obvious that my recollection was flawed in the extreme. El-Cheapo was nothing like the circuit here, and is now available as Project 12A. The amplifier design(s) here have been preserved...
Craig Maynard dreamed up the Chloroplast solar engine (an interesting design, tho' it uses two parts you probably won't have sitting around in your parts drawer). Since I really can't describe it better than Craig can, here's his description (from the Chloroplast web site), followed up by commentary and a related circuit by Wilf Rigter:..
Simple microphone preamplifier which enable using dynamic microphone with Sound Blaster card. Sound blaster sound card series (SB16, SB32, AWE32 and AWE64) have all a microphone input designed to be used with the electret microphones which come with the sound card package (some packages) or with separate microphone designed to be used with Sound Blaster sound cards (there are separate microphones and some monitors have built-in microphones like this)...
This is just one of the many bugging devices available on the eaves-dropping market. The range includes pen and pencil holders, trophies, framed pictures and office furniture with false bottom drawers. These products are readily sold to fledgling companies, eager to nestle into big brother's market. And for a while these bugging devices worked. Few firms knew of their existence, and even less on how to sniff them out. But that has all changed now. If a corporation.....
And my recent study about chaos is really making me have FUN! The subject is awesome! And my Geeky Bro informed me something about a cell phone jammer, a simple timer circuit using 555. Will work within 10 feet maybe, LOL:) Anyone should get a book to get started and they should get a taste on the subject. Recommended Chaos” By Lenny Smith From Oxford University Press’s Very Short Introduction series. I started reading this book...
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