The CPU is an AMD K5 running 75 MHz. Theres 16 meg ram, and the operating system is Linux (Red Hat 5.2). MPG123 handles the MP3 decoding, and I wrote a control program in Perl. I built the remote control in an old Blaupunkt CD-changer remote case which I....

Controller for brushless and sensorless motors, with active rpm control # Active rpm control # Car mode # Proportional brake # Active freeweehling # Updates via Internet available..

The Above circuits are based on TEA2025 is a monolithic integrated audio amplifier in a 16-pin plastic dual in line package manufactured by UTC .Circuit has an Internal Thermal Protector. It is designed for portable cassette players and radios. You can also....

The protection circuit output amplifiers and speakers, has some interesting features such as isolating the speaker from the amplifier output when shown a continuous trend in output or when the temperature gets too much cooler while providing a time delay and....

A battery is a vital element of any battery-backed system. In many cases the battery is more expensive than the system it is backing up. Hence we need to adopt all practical measures to conserve battery life. As per manufacturer's data sheets, a 12V....

This circuit uses a single chip, IC BA3812L for realizing a 5 band graphic equalizer for use in hi-fi audio systems.The BA3812L is a five-point graphic equalizer that has all the required functions integrated onto one IC. The IC is comprised of the five tone....

If you do not like the whip antenna on your car, you may try this alternative circuit. A one-turn loop is installed in the windscreen of the car, keeping possibly away from the metal structure of the car. This loop is terminated in a 6.5mm ring core suitable....

The circuit in Figure 1 allows you to light any type of LED from a single cell whose voltage ranges from 1 to 1.5V. This range accommodates alkaline, carbon-zinc, NiCd, or NiMH single cells. The circuit`s principal application is in LED-based flashlights,....

It's a great convenience that most modern cars come with a built in alarm, however it is nothing but noise pollution that the horn sounds when the alarm is armed. Disconnecting the alarm system from the horn relay will eliminate this, but prevent the horn....

This charger will quickly and easily charge most any lead acid battery. The charger delivers full current until the current drawn by the battery falls to 150 mA. At this time, a lower voltage is applied to finish off and keep from over charging. When the....

The 24 watt amp is easy to build, and very inexpensive. The circuit can be used as a booster in a car audio system, an amp for satellite speakers in a surround sound or home theater system, or as an amp for computer speakers. The circuit is quite compact and....

Easy to build, this high voltage generator is capable of generating up to 50KV but the breakdown voltage of the coil limits the voltage to a value somewhat lower. T2 is the ignition coil of a car and also the 0.5µF capacitor comes from the same place:....

This circuit is very basic to build and puts out great power for your car or home. Keep all leads as short as possible...

This circuit will flash a super-bright LED (5000+ mcd). Good for fake car alarm or other attention getting device. Component values are not critical, try anything else first from your junkbox. Obviously, the 470 ohm resistor (R3) determines the LED's....

A good way to mount the circuit board is to use a hot glue gun to "mold" the circuit underneath the lamp housing. There is plenty of space there for your board. At the next photos you can see the circuit board mounted on the small 31cm IKEA Mylonit Lamp.....

A Selective Amplifier 10dB for FM/VHF region. Note that some devices to be used SMD components and may have a minimum sales volume. Device works very well as an FM external amplifier "when used for example in car / boat etc . Thanks to GF3 filter, amplifier....

Proposed power supply for amplifier 100W v-mosfet [ 1 ] is what appears in the above form. It has separated supply for the various stages of supply, stage for power, stage for control, supply for preamplifier and for stage of protection. Whoever wants it can....

This is a 40 meter transmitter which uses two valves, the 6AU6 and 6GV8. The construction is easy. Just be carefull due to high voltage present...

The approaches using on-chip A-to-D converters on AVR, PIC, and Cypress controllers reached sample rates of up to about 60 kHz. Not really very useful for the sort of thing I was thinking about using this for: encoded data, radio control signals, A-to-D....

This paper describes an RF amplifier circuit which is suitable for the frequencies between 10MHz and 500MHz. These kind of amplifiers are called wide band amplifiers. Wide band amplifiers are used in communication receivers, RF measuring equipment and....

The Inter-Power SWR-5 - upper right - "isn't worth a penny". Got it from a mate to use with a beacon, but I burnt it out with only 3.5-4W morse signal on 70cm. Removed the bridge and installed my own pick-up line (suggested by LA8OJ) and now it is fb for....

Vacuum Tubes 807 and 1625 are commonly used by hams as power amplifiers. Both tubes are audio power amplifier beam tetrodes in the output stage of high power amplifiers but they are suitable for high frequencies also. Both tubes are equal in their....

The purpose of this circuit is to animate shop-windows by means of a capacitive sensor placed behind a post-card-like banner. The card is placed against the glass inside the shop-window, and the visitor can activate the relay placing his hand on the card,....

This is the basic interface I used as part of my Computerized Room project. This is the parallel interface only. The 8 bit input card can be found, along with the rest of the project, at Computerize Your Room/House. This interface, as well as the other two....

Most cards of sound in computer, are deprived stereo input for microphone, on the contrary have stereo input for high level [ Line ]. The circuit uses the input Line of card of sound, in order to we place a two mono stereo microphone, in the input of card of....

When the brake pedal is on depressed, battery positive voltage normally applies through the STOP fuse and stop light switch to terminal STP of the ECU, and the ECU turns the cruise control off. A failsafe function is provided so that cancel functions....

A three-dimensional surround sound Ambisonic recording can be captured using a tetrahedrally arranged quartet of cardioid pattern microphone capsules connected to some simple circuitry to convert the outputs to a standard B-format signal. B-format signals....

One-farad capacitors require some care. It`s a common knowledge that they must be pre-charged with a current-limiting resistor before plugging in. It is less common knowledge that those fifty-dollar `smart cap controllers` are in fact very simple devices,....

Only one out of 9,999 possible codes has the power to unlock this simple, yet effective, electronic lock. A combination lock is not just a perfect system to protect your belongings, it is also a valid system to let everyone to know that you are vigilant: an....

Loop Antennas are considered to be "samall" when their diameter drops below about 1/10 of the wavelength they are intended to be used at. In this case, I use the term "Tiny" because the antenna's diameter is about 1/30,000 the wavelength, and at 5.5 cm in....

This is a special low voltage version of my audio preamp. T1`s emitter voltage is biased close to half supply voltage (1.5V) to allow for maximum output voltage swing. Both transistors are direct coupled and have closed loop feedback to aid temperature....

For normal use it`s necessary to connect the battery, when the jumper is connected. Please take care, that the transmitter is on and the throttle is set to "power off"...