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August 7, 2010
Three 2nd order filters are shown, low pass, high pass, and bandpass. Each of these filters will attenuate frequencies outside their passband at a rate of 12dB per octave or 1/4 the voltage amplitude for... [more]
December 13, 2010
The circuit is a microphone amplifier for use with low impedance (~200 ohm) microphones. It will work with stabilized voltages between 6-30VDC. If you don't build the impedance adapter part with T1, you get a... [more]
August 6, 2010
The example below illustrates using an op-amp as an audio amplifier for a simple intercom. A small 8 ohm speaker is used as a microphone which is coupled to the op-amp input through a 0.1uF... [more]
October 4, 2010
Although modern integrated circuit operational amplifiers ease linear circuit design, IC processing limits amplifier output power. Many applications, however, require substantially greater output voltage swing or current (or both) than IC amplifiers can deliver. In... [more]
circuit from:http://www.extremecircuits.net/2010/05/op-amp-booster-designs.html
September 27, 2010
ICs that in the past were far too expensive for the hobbyist tend to be more favourably priced these days. An example of this is the AD8099 from Analog Devices. This opamp is available for... [more]
circuit from:http://www.extremecircuits.net/2010/05/opamp-vhf-fm-transmitter.html
December 29, 2010
The op-amp is basically a differential amplifier having a large voltage gain, very high input impedance and low output impedance. The op-amp has a "inverting" or (-) input and "noninverting" or (+) input and a... [more]
October 15, 2010
This circuit is mainly intended to provide common home stereo amplifiers with a microphone input. The battery supply is a good compromise: in this manner the input circuit is free from mains low frequency hum... [more]
September 26, 2010
This circuit is mainly intended to provide common home stereo amplifiers with a microphone input. The battery supply is a good compromise: in this manner the input circuit is free from mains low frequency hum... [more]
circuit from:http://www.extremecircuits.net/2009/12/portable-microphone-preamplifier.html
December 28, 2010
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... [more]
August 7, 2010
A bandpass filter passes a range of frequencies while rejecting frequencies outside the upper and lower limits of the passband. The range of frequencies to be passed is called the passband and extends from a... [more]
October 4, 2010
Typically the op-amp's very large gain is controlled by negative feedback, which largely determines the magnitude of its output ("closed-loop") voltage gain in amplifier applications, or the transfer function required (in analog computers). Without negative... [more]
circuit from:http://www.extremecircuits.net/2010/05/upto-73-op-amp-circuit-collection-pdf.html
December 28, 2010
The sunset lamp comes on at full brightness and then slowly fades out over 1.5 hours time and stays off until power is recycled. [more]
October 13, 2010
The circuit will give us 10 amps (12 amps surge) with performance that equals or exceeds any commercial unit. The circuit even has a current limiting feature which is a more reliable system than most... [more]
June 22, 2010
This is a 100 watt basic power amp that was designed to be (relatively) easy to build at a reasonable cost. It has better performance (read: musical quality) than the standard STK module amps that... [more]
June 22, 2010
This design is based on the 18 Watt Audio Amplifier, and was developed mainly to satisfy the requests of correspondents unable to locate the TLE2141C chip. It uses the widespread NE5532 Dual IC but, obviously,... [more]
June 22, 2010
Using a single 7812 IC voltage regulator and multiple outboard pass transistors, this power supply can deliver output load currents of up to 30 amps. [more]
December 27, 2010
Here is a 12 volt / 2 amp lamp dimmer that can be used to dim a standard 25 watt automobile brake or backup bulb by controlling the duty cycle of a astable 555 timer... [more]
December 28, 2010
The full wave phase control circuit below was found in a RCA power circuits book from 1969. The load is placed in series with the AC line and the four diodes provide a full wave... [more]
December 28, 2010
This circuit is basically the same as the 10 channel LED sequencer with the addition of solid state relays to control the AC lamps. The relay shown in the diagram is a Radio Shack 3... [more]
June 22, 2010
It uses a normal 120 to 6V stepdown transformer in reverse to step 12V to about 350V to drive a lamp without the need to warm the filaments. [more]
August 6, 2010
2 x 18W Hi-Fi Stereo Power Amplifier based around two TDA2030 ICs. It has good input sensitivity, low distortion, good operating stability and full protection against overloads and output short-circuits. It can be used as... [more]
circuit from:http://www.extremecircuits.net/2010/01/18w-18w-stereo-hi-fi-audio-amplifier.html
June 22, 2010
Can be directly connected to CD players, tuners and tape recorders. [more]
August 6, 2010
High Quality very simple unit, No need for a preamplifier [more]
circuit from:http://www.extremecircuits.net/2009/07/18watt-audio-amplifier.html
June 22, 2010
The amplifier is a circuit of high frequency RF with distinguishable materials. The amplifier as circuit strengthens the tendency of signal with concrete aid, depending on the frequency of signal. [more]
June 22, 2010
The 22 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... [more]
December 11, 2010
This circuit is intended as a reliable replacement to thermally-activated switches used for Christmas tree lamp-flashing. [more]
September 30, 2010
Due to the low current drawing, the circuit can be supplied from 230Vac mains without a transformer. Supply voltage is reduced to 12Vdc by means of C1 reactance, a two diode rectifier cell D1 &... [more]
circuit from:http://www.extremecircuits.net/2009/07/220v-ac-lamp-toggle-switch.html
August 6, 2010
This is a 25 Watt basic power amp that was designed to be (relatively) easy to build at a reasonable cost. It has better performance than the standard STK module amps that are used in... [more]
circuit from:http://www.extremecircuits.net/2009/07/25-watt-audio-amplifier-circuit.html
June 22, 2010
Can be directly connected to CD players, tuners and tape recorders. Simply add a 10K Log potentiometer (dual gang for stereo) and a switch to cope with the various sources you need. [more]
June 22, 2010
Simple and low cost. The optimal supply voltage is around 50V, but this amp work from 30 to 60V. [more]
August 5, 2010
This amplifier was designed to be self-contained in a small loudspeaker box. It can be feed by Walkman, Mini-Disc, iPod and CD players, computers and similar devices fitted with line or headphone output. Of course,... [more]
circuit from:http://www.extremecircuits.net/2009/07/2watt-audio-amplifier.html
August 6, 2010
Here is a little audio amplifier similar to what you might find in a small transistor radio. The input stage is biased so that the supply voltage is divided equally across the two complimentary output... [more]
August 5, 2010
The Power Amplifier section employs only three transistors and a handful of resistors and capacitors in a shunt feedback configuration but can deliver more than 18W into 8 Ohm with 0.08% THD @ 1KHz at... [more]
circuit from:http://www.extremecircuits.net/2009/12/30-watt-audio-power-amplifier-schematic.html
August 5, 2010
It's based on a Philips class-H audio amplifier IC and can deliver 36W RMS OR 70W music power, all from a 13.8V supply. Our new Mighty Midget Amplifier can really pack a punch - around... [more]
August 5, 2010
These goals were achieved by using a discrete-components op-amp driving a BJT complementary common-emitter output stage into Class B operation. In this way, for small output currents, the output transistors are turned off, and the... [more]
circuit from:http://www.extremecircuits.net/2010/02/45-watt-class-b-audio-power-amplifier.html
August 5, 2010
This solid-state push-pull single-ended Class A circuit is capable of providing a sound comparable to those valve amplifiers, delivering more output power (6.9W measured across a 8 Ohm loudspeaker cabinet load), less THD, higher input... [more]
circuit from:http://www.extremecircuits.net/2009/07/5-watt-class-audio-amplifier-circuit.html
June 22, 2010
This circuit is of an 2x 2,500W RMS stereo amplifier, super-light and without switching-mode power supply [more]
June 22, 2010
This is a handy, easy to build general purpose 50 watt amp. The amp has an input for a radio, TV, stereo or other line level device. [more]
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