4 x 4-400A HF LINEAR

Aug 091000Watt Power Amplifier

 AUDIO AMPLIFIER BTL

Audio amplifiers operate either in a BTL (bridged) or single-ended (“normal”) configuration. In the single-ended setup, the output lead goes to the “hot” or “+” side of the load (speaker or speaker box since we are talking audio) and the “-” or “negative” side of the load is tied to a common ground shared with the amplifier. In the BTL configuration, one amp is connected to the “+” side of the speaker (load) and a second amp is connected to the “-” side of the load. For this to work, the output signal from the second amplifier must be a “mirror image” (identical in every respect, but 180 degrees out of phase) of the output from the first amp. The BTL configuration is most often seen in low-voltage, battery-powered applications (like cell phones or “walkman” type personal tape or cd players etc) or in automotive applications over about 10 watts per channel.

In the BTL configuration, each amp drives half the load impedance. With the signals being out of phase, the voltage swing across the load appears to be doubled, and with each amp driving half the impedance the current is doubled. In theory the bridged pair will produce 4 times the power into the load that either amp acting alone could provide. In reality it seldom works that well.

This is an power amplifier circuit of a BTL system, which comprises a first op-amp chip which outputs an output signal having a same phase as an input signal input to a signal input terminal, a second operational amplifier which outputs an output signal having an opposite phase to the input signal, a voltage divider which generates a midpoint voltage of the input signal, a first resistor connected between an output terminal and a negative phase input terminal of the first operational amplifier, second and third resistors connected in series between the negative phase input terminals of the first and second operational amplifiers, a fourth resistor connected between an output terminal and the negative phase input terminal of the second operational amplifier, and an impedance converter connected between a midpoint voltage node of the voltage divider and a series-connection node of the second and third resistors. (end of abstract)

Gambar Rangkaian Power Amplifier BTL

List Componet:
R1, R2,R3, R4, R6………………… 10kOhm.
R3……………………………………… 20kOhm.
C1, C2, C3, C4……………………… 10µF.
Catu daya (VCC) ±12 V.

There are some important updates to this project, as shown below. Recent testing has shown that with the new ON Semi transistors it is possible to obtain a lot more power than previously. The original design was very conservative, and was initially intended to use 2SA1492 and 2SC3856 transistors (rated at 130W) – with 200W (or 230W) devices, some of the original comments and warnings have been amended to suit.

Skema Rangkaian 500Watt Power Amplifier

Note:

• This amplifier is not trivial, despite its small size and apparent simplicity. The total DC is over 110V (or as much as 140V DC!), and can kill you.
• The power dissipated is such that great care is needed with transistor mounting.
• The single board P68 is capable of full power duty into 4 Ohm loads, but only at the lower supply voltage.
• For operation at the higher supply voltage, you must use the dual board version.
• There is NO SHORT CIRCUIT PROTECTION. The amp is designed to be used within a subwoofer or other speaker enclosure, so this has not been included. A short on the output will destroy the amplifier.

Please note that the specification for this amp has been upgraded, and it is now recommended for continuous high power into 4 Ohms, but You will need to go to extremes with the heatsink (fan cooling is highly recommended). It was originally intended for “light” intermittent duty, suitable for an equalised subwoofer system (for example using the ELF principle – see the Project Page for the info on this circuit). Where continuous high power is required, another 4 output transistors are recommended, wired in the same way as Q9, Q10, Q11 and Q12, and using 0.33 ohm emitter resistors.
Continuous power into 8 ohms is typically over 150W (250W for ±70V supplies), and it can be used without additional transistors at full power into an 8 ohm load all day, every day. The additional transistors are only needed if you want to do the same thing into 4 ohms at maximum supply voltage! Do not even think about using supplies over ±70V, and don’t bother asking me if it is ok – it isn.

Aug 09

1000Watt Power Amplifier

This is a circuit of 1000watt power amplifier. This time I don’t have a picture to the circuit board, but because the amplifier circuit is quite simple, you can design it yourself PCB easily or you can order it at the store PCB audio kit in the center of electronic singosaren oriental, solo.

Skema Rangkaian Sanken 1000 watt

The assemble cables for DC power supply and output transistors must be large, use size 1.5-3mm for large current passed. The supply used transformer with 20A/45Ct and at least 4×10000uf/80 volt capasitor. this circuit is able to supply power 10000watt therefore the power transistor will be very hot, give good cooling fan on the power transisitor

Transitor alternative to replacement of the 2SA1494 is 2SA1216 From SANKEN. The transistor has a 200-350 watt power dissipation of each pair so that for long-term operation of more durable. Keep in mind, usually sold a pair of power transistors with its complement, so you can not buy 2SC2922 alone without 2SA1216 or 2SA1494 without 2SC3858. The price range for transitor tsb is 30-40 thousand Rupiah / pair.

Aug 09

Power Amplifier MJ15003 -MJ15004

When I began the design of this amp, my goal was to make a product better suited for the reproduction of complex music and voice. Although I emphasize the high electrical properties, the most important requirement is to create a superior sound, vivid images and superb spatial aural clarity.Although the average level of listening is usually less than 10 watts, my design concept was to an amplifier with plenty of reserves, but the deviation is for Class A, at the height of the audience of cross-over distortion at a very low level. There is no place in the pathway, enhances the precision of the tonal characteristics of instruments and voices clearly. This Amplifier is virtually zero phase distortion over the audio range resolution is perfect and completely color the sound.

Skema Rangkaian Power Amplifier MJ15003 -MJ15004

Amplifier Specification:
Maximum Output: 240 watts rms into 8 Ohms, 380 watts rms into 4 Ohms
Audio Frequency Linearity: 20 Hz – 20 kHz (+0, -0.2 dB)
Closed Loop Gain: 32 dB
Hum and Noise: -90 dB (input short circuit)
Output Offset Voltage: >13 mV (input short circuit)
Phase Linearity: > 13 0 (10 Hz – 20 kHz)
Harmonic Distortion: > 0.007% at rated power
IM Distortion: > .009% at maximum power

2000Watt Power Amplifier

Thursday, April 8th, 2010

This power amplifier circuit provides up to 2000Watt, it has to be said that this amplifier will blow up any speaker connected to it. I recommend this as a ‘thought experiment’, rather than actually doing it!. 110V RMS into 8 ohms is 1500 W. How long would you expect the speaker to last? Most will be toast within perhaps 30 seconds or less!

Skema rangkian power amplifier sound system 2000 watt

The transistor Q5 (the bias servo transistor) is mounted on the heatsink, in excellent thermal contact. This is because, unlike most of my other designs, this amp uses conventional Darlington output configuration. It is necessary to use a Darlington arrangement (or a low power Darlington transistor as shown) for Q5 to ensure that the bias remains at a safe value with temperature. There is probably good cause to model and test this aspect of the design very carefully, because it is so important. The arrangement as shown will reduce quiescent current at elevated temperatures. For example, if total Iq at 24°C is 165mA, this will fall to ~40mA at 70°C. This is probably fine, because there is some delay between the a power ’surge’ and the output transistors transferring their heat to the bias servo via the heatsink.

The power supply needed for an amp of this size is massive. Grown welding machines will look at it and cry. For intermittent operation, you need a minimum of a 1000VA transformer (or 1500VA for the 2000W version), and it will have to be custom made because of the voltages used. If you expect to run the amp at continuous high power, then transformers should be 2kVA and 3000VA respectively. Filter capacitors will pose a problem – because you need caps rated for 150V, these will be hard to find. Because high voltage high value caps can be difficult to find, it may be necessary to use two electros in series for each capacitor location. This is the arrangement shown. You must include the resistors in parallel – these equalise the voltage across each capacitor so that they have the same voltage. Remember to verify the ripple current rating! This can be expected to be over 10A, and under-rated capacitors will blow up.

Skema Rangkian Power Supplay 2000 VA

WARNING
This project describes an amplifier, power supply and tests procedures that are all inherently dangerous. Nothing described in this article should even be considered unless you are fully experienced, know exactly what you are doing, and are willing to take full 100% responsibility for what you do. There are aspects of the design that may require analysis, fault-finding and/or modification

Under The Cover’s 2m Discovery

Sumber :linear AMP uk

Stereo Test Tone Generator

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Stereo Test Tone Generator

(C) G. Forrest Cook May 5, 2003

Introduction

This circuit produces two audio frequency sine waves with different frequencies but equal amplitudes. It can be used for testing a variety of stereo audio equipment. The circuit was originally developed the purpose of aligning an FM Stereo Modulator, like the type used in low power FM stereo transmitters. Two tone outputs are available, the low tone has a secondary output that is 180 degrees out of phase with the primary output. The circuit is also handy for testing computer sound card inputs. A variety of waveform configurations can be produced by plugging a stereo audio patch cord into the four output jacks.

Specifications

Operating Voltage: 12V DC (should work ok on 9V)
Operating Current: 15ma max.
Low Output Frequency: approximately 600 Hz
High Output Frequency: approximately 800 Hz
Output Levels: approximately 0.5V - 5V P-P

Theory

IC U3B is wired to produce a virtual ground at half of the power supply rails (6V). This is used elsewhere in the circuit as a reference. The power supply is filtered with the 220uF capacitor. The 3A crowbar diode offers some protection against reverse polarity on the power inputs. For full protection, place a 1A or smaller fuse in series with the +12V input. The circuit has two nearly identical stereo sine wave generator circuits. U1 is the low tone oscillator, U2 is the high tone oscillator. The two op-amps on the left of each oscillator chain produce square and triangle waveforms at fixed frequencies. The frequency is set with the 10n and 6n8 capacitors.
The triangle waves are passed into low-pass filters, which remove most of the harmonic energy and produce relatively pure sine waves. The two 27K and two 33K resistors set the low pass frequency.
The sine waves are each fed into an output amplifier which can be adjusted for fixed level outputs. The low tone output is also fed into IC U3A which produces an inverted copy of the low tone signal.

Construction

The circuit was built on a piece of perforated prototyping circuit board. Wiring was done by hand using bare tinned copper wire covered with small pieces of teflon insulation. The circuit board and connectors were mounted on a piece of bent plastic, this protects the board from shorting out.

Alignment

Connect an oscilloscope to the low tone output and adjust the low tone output level for a specified level, I used 4V peak-to-peak. Connect the oscilloscope to the high tone output and adjust the high tone output level to the same level as the low tone oscillator.
Connect the oscilloscope to the inverted low tone output and adjust the invert level for the same level as the low tone output. If you have a two channel oscilloscope, connect one channel to the low tone output, connect the other channel to the inverted low tone output. Set the scope to add the channels with one of the channels inverted, then adjust the invert level control for the best null.
The circuit is not particularly stable over a wide range of temperatures. If you are using it for precision level setting, align it prior to each use. For most audio work, the alignment only needs performing one time. For the best stability, use high quality capacitors for the oscillator and filter sections.

Use

There are three stereo signal combinations that can be generated with this circuit. For a mono test signal, connect both channels to the two low tone outputs. For a stereo two tone test signal, connect one channel to the low tone output and the other channel to the high tone output. For a two phase one tone test signal, connect one channel to the low tone output and the other channel to the inverted low tone output.

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  Sumber :  FC's Electronic Circuits

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High Fidelity FM Stereo Modulator

High Fidelity FM Stereo Modulator (Rev E)

This page was last modified on April 14, 2008.

Rev E Design

This circuitry is used for generating a high quality FM stereo multiplex signal that is suitable for driving mono FM transmitters. The Rev E FM stereo multiplex generator is the most recent design in a series of circuits that have appeared on this site. The older designs should now be considered obsolete. This version features improvements to the audio mixer stage, better gain adjustments in the audio filter stage and a rework of the multiplexer stage. When it is adjusted properly, the Rev E design produces an FM stereo signal with excellent fidelity. The Free Radio Berkeley 1W "No Tune" PLL synthesized unit (year 2000 version) was used as the transmitter for this project. If you use the FRB board, these modifications should be performed on the transmitter. Wavematch Communications has a 2W mono FM transmitter that looks like it would work with this circuit, some audio front-end mods may be required. The modifications involve the removal of the audio input filtering components and the addition of an input level control. The input filter mod allows the 19Khz and 38Khz signals to pass through to the transmitter's modulation stage.
For the best signal coverage, an efficient and properly tuned antenna is a must. This J-Pole antenna works quite well and can be grounded for some protection against lightning.
It is a good idea to have a stereo compressor between the signal source and the transmitter, when properly set, it can save the operator from having to "ride" the volume level between the point of good modulation and the point of distortion. The Alesis 3630 compressor looks like it would be a good choice, although this has not been tried. This circuit does not perform pre-emphasis (high frequency boosting), a graphic equalizer in front of the compressor can be used if desired.
This is a fairly high-level project, it should only be attempted by someone with a fair amount of electronics experience. A decent oscilloscope and an audio signal generator are necessary for aligning this circuit.
It is the operator's responsibility to run the transmitter in accordance with the frequency regulating authority of their country, it may be necessary to use an output attenuator on some transmitters.

Theory

The mixer stage involves a passive circuit for the two stereo inputs. The microphone signal is first boosed with two stages of op-amps, then split into the left and right channels with a double 10K audio taper potentiometer. The two stereo inputs are filtered for RF energy with LC Pi filters. The outputs of the stereo input and mic volume controls are padded with 5.1K resistors, this prevents the control from one channel pair from changing the volume of another channel pair at the top settings. The left and right signals are fed through individual master volume controls, these can be used to set the maximum signal level and balance the channels. The 2K pad resistors on the master volume controls prevent scratchy sounds that show up when turning the controls all the way up. The stereo audio filter board has two filter stages and transistor buffer stages that provide isolation and gain between the filter stages. The audio signal is amplified, run through a three pole low pass filter, buffered again, then run through a 19Khz notch filter. The 19Khz filter enhances the cutoff of the low pass filter in the frequency range between 15Khz and 19Khz. The LM833N driver amplifiers increase the audio signal level and provide DC drive to the following LM833N sum/difference amplifiers.
The FM stereo modulation waveform consist of a mono (Left + Right) baseband audio signal plus a (Left - Right) AM-modulated 38Khz subcarrier signal plus a 19Khz sine wave pilot tone.
The L-R mixer amplifier is a difference amplifier, it produces the signal that is used to modulate the 38Khz wave via the LM13700 modulator. The L+R+19K+38K mixer amplifier combines the Left and Right baseband audio signals with the 19Khz pilot tone and the 38Khz AM modulated subcarrier to produce the multiplex output signal. It should be noted that the 38Khz signal should really be double sideband supressed carrier (DSB-SC) modulated instead of AM modulated. The next version of this circuit will probably involve replacing the LM13700 IC with a double balanced mixer such as the LM1496 or possible the NE602. Meanwhile, the circuit shown performs well, and is sufficient for low power FM transmitters.
The 38Khz oscillator produces a square wave signal, that is fed to the 4013 flip-flop IC which divides the frequency in half to produce 19Khz. The 38Khz and 19Khz square wave signals are fed to two L-C resonant circuits to produce sine wave signals. The two sine waves are amplified by the sine wave buffer ICs to produce 38Khz and 19Khz sine waves. The 19Khz sine wave is fed to the L+R+19K+38K mixer. The 38Khz sine wave is fed to the carrier input of the LM13700 modulator.
The VU/clipping meter combines the left and right audio signals from the driver amplifier outputs in the TL071 summing amplifier. The combined signal is amplfied by the TL071, then fed to the LM3916N VU meter IC. The colored LEDs are wired as a 5 stage VU meter, the upper 5 stages are connected to the white Clipping indicator LED. The LM3916N is wired to be in the dot display mode, the parallel connections to the white LED cause the LED to light for all levels above clipping, making the clipping indication more visible. Power to the LEDs is taken from the unregulated 12V supply to keep the LED switching noise off of the audio amplifier supply.
The power supply is not shown on the schematic. A 12VDC source is required, this can be anything from a lead acid battery to a wall-wart to a standard analog power supply. Beware that most wall-warts have misleading voltage ratings. The power supply should be rated to produce at least 2 amps. This source is tied to the +12V unregulated inputs.
The +/- 12V regulated supplies come from a MeanWell model DKE15A-12 DC-DC converter supplied by the +12V unregulated supply. Jameco.com sells these devices. This allows the transmitter to be run from a single 12V source such as an automobile or a battery. One +12V/-12V regulated line powered power supply could be used to power the whole transmitter, just tie the +12V regulated and +12V unregulated lines together.
See the Wikipedia article on FM modulation for reference information.

Alignment

Alignment of this circuit requires putting two sine waves of differing audio frequencies into the audio input. This Stereo Test Tone Generator circuit works well for the job. Other sine wave sources can be a pair of audio test generators, one or two PCs running sine wave generator software, or a test tone CD. The sine waves should be connected to the left and right inputs of the mixer board and the levels should be adjusted to 0.2V on the audio input of the multiplexer board. An oscilloscope should be connected to the various test points (tp-#) on the low pass and notch stages, the gains of each stage should be adjusted so that the peak-to-peak sine wave values match the values shown on the schematic for tp1, tp2 and tp3. If properly adjusted, tp1 through tp3 (left and right) should show distortion-free sine waves.
The 38Khz and 19Khz coils should be adjusted for peak values on tp9 and tp8. The scope should be put on tp12 and the carrier level should be adjusted a bit below the point where the 38Khz wave shows no clipping. The carrier bias adjustment and 38K modulation controls are interactive, both should be set so that the modulated 38Khz signal is just below 100% modulation on tp12. All waveforms should be sine, not square. The 19Khz pilot level should be set to 3V p-p on tp8. A properly adjusted modulator should produce only "pretty" sinusoidal waveforms on tp12 and tp4. If the waveforms look square or non-sinusoidal, the transmitter's output will be distorted.
The audio peak level meter should be adjusted so that the white clipping LED just starts to light when the rest of the circuit is running at 100% modulation.
Lastly, the input level adjustment shown in the FRB modification schematic should be adjusted. Run the transmitter into a dummy load and listen to the signal in a nearby FM stereo radio through headphones if possible. With dual sine waves input to the mixer and modulation at 100%, adjust the transmitter input level to the point of audible distortion, then back off a small amount. It can be helpful to increase the sine wave input to purpously cause audible distortion, then tweak the transmitter input volume to the point below where the broadcast sounds "harsh".
Connect a stereo music source to the audio inputs. The signal on the FM receiver should be stereo. If the alignment steps were carried out correctly, the received signal should not be distorted as long as the clipping indicator is off.

Sumber : Low power FM Stereo Radio Station