Rangkaian 500Watt Power Amplifier

500Watt Power Amplifier

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.

READMORE...

Rangkaian Amplifier Mosfet 60watt

Amplifier Mosfet 60watt

The following is a 60 - 90W High Quality power amplifier. Circuit topology is about the same of the above mentioned amplifier, but the extremely IRFP9240 Rugged IRFP240 MOSFET devices and are used as the output pair, and well Renowned high voltage Motorola's transistors are employed in the preceding stages. The supply rails prudentially voltage was kept at the rather low value of + and - 40V. For those wishing to experiment, the supply voltage rails could be raised to + and - 50V maximum, allowing the amplifier to approach the 100W into 8 Ohm target

Skema Rangkaian 60watt Amplifier Mosfet

Note:

• A small, U-shaped heatsink must be fitted to transistor Q6 & Q7.
• Mosfet Q8 & Q9 must be mounted on large heatsinks.
• Quiescent current can be measured by means of an Avo-meter wired in series to the positive supply rail and no input signal.
• Set the Trimmer R10 to its minimum resistance.
• Power-on the amplifier and adjust R10 to read a current drawing of about 120 - 130mA.
• Wait about 15 minutes, watch if the current is varying and readjust if necessary.

List Component:
R1_______________47K 1/4W Resistor
R2_______________4K7 1/4W Resistor
R3_______________22K 1/4W Resistor
R4_______________1K 1/4W Resistor
R5,R12,R13_________330R 1/4W Resistors
R6_______________1K5 1/4W Resistor
R7_______________15K 1/4W Resistor
R8_______________33K 1/4W Resistor
R9_______________150K 1/4W Resistor
R10______________500R 1/2W Trimmer Cermet
R11______________39R 1/4W Resistor
R14,R15___________R33 2.5W Resistors
R16______________10R 2.5W Resistor
R17______________R22 5W Resistor (wirewound)
C1_______________470nF 63V Polyester Capacitor
C2_______________470pF 63V Polystyrene or ceramic Capacitor
C3_______________47µF 63V Electrolytic Capacitor
C4,C8,C9,C11________100nF 63V Polyester Capacitors
C5_______________10pF 63V Polystyrene or ceramic Capacitor
C6_______________1µF 63V Polyester Capacitor
C7,C10____________100µF 63V Electrolytic Capacitors
D1_______________1N4002 100V 1A Diode
D2______________5mm. Red LED
Q1,Q2,Q4__________MPSA43 200V 500mA NPN Transistors
Q3,Q5____________BC546 65V 100mA NPN Transistors
Q6______________MJE340 200V 500mA NPN Transistor
Q7______________MJE350 200V 500mA PNP Transistor
Q8______________IRFP240 200V 20A N-Channel Hexfet Transistor
Q9______________IRFP9240 200V 12A P-Channel Hexfet Transistor

READMORE...

Rangkaian Subwoofer Controller

Subwoofer Controller

Subwoofer controller is quite simple, an input buffer provides phase switching and ensures that the input impedance of the source does not affect the filter performance, and this is nowfollowed by a 12dB/octave high pass filter. The phase reverse switch is used so that the sub can be properly phased to the rest of the system. If the mid-bass disappears as you advance the level of control, then the phase is wrong, so just switch to the opposite position.Contribute a better translation

The board has only one input, so if you plan to use a normal stereo feed supplying a single P48 board, you'll need to sum the two stereo outputs. This is easily accomplished by using a pair of resistors - the value should be between 2.2k and 4.7k. If this is done, replace R1 with either a 100 ohm resistor or a wire link.

Skema Rangkaian subwoofer Controller

VR1 is used to change the gain of the second integrator. The level through the controller can be set to make sure that there is no distortion - there can be a huge amount of gain at low frequencies, and if the gain is too high, distortion is assured!

The high-pass filter is designed as a peaking type, and gives a response that is almost perfect down to 20Hz. The lowest frequency can be tailored by changing C1, C2, C3 and C4. As shown, the response peaks at 18Hz, but you can use 68nF to increase this to 27Hz, or 47nF for 39Hz. See Table 1 for the full range of values.

The integrators (U2B and U2A) include shelving resistors (R8 and R11), and the capacitor / resistor networks (C3-R9, C4-R12) allow the HF attenuation to be halted at a specific frequency.

Important:

The unity gain frequency is important in only one respect - it will determine the internal gain of the system, and needs to be set based on the input signal level. If the unity gain frequency is set to (say) maximum (68Hz) and you have a 1V RMS input, then a 1V RMS input at 20Hz will severely clip the integrators. The setting for VR1 is determined by the input sensitivity of your power amplifier(s) used on the main system. It is probably easier to experiment a little than try to measure everything.

More detail

READMORE...

Rangkaian Audio Limiter Berbasis Op-Amp

Audio Limiter Berbasis Op-Amp

This audio peak limiter employs a FET as a variable resistance to attenuate the input signal according to a control voltage (CV). It offers unusually good performance with low cost and component count. A TL072 dual opamp (U1) provides the circuit gain and full wave peak detection.

Skema Rangkaian Audio Limiter Berbasis Op-Amp

If desired, a LED VU meter may be used here instead, and with proper calibration will give a good indication of the peak attenuation at any time. This option will require some experimentation from the constructor, and further details are up to the individual to work out.

The 4.7K resistor and 1uF capacitor (R14 and C5) determine the attack time, which is about 5ms as shown. R12 and C5 determine the release or recovery time, and as shown this is approximately 1 second.

R11, C3 C4 and R13 form the distortion cancelling circuit, and as can be seen, the control voltage impedance is very low compared to the distortion cancellation impedance, so the circuit's attack time is not compromised. The values of resistance and capacitance have been optimised for the least distortion across the audio band, at 0.3% THD typical for frequencies above around 500 Hz, at 1.65V RMS output level. Below 500 Hz, the distortion rises gently with decreasing frequency, but also falls with lower voltages. Distortion is negligible at any voltage level below the limiting threshold.

Be careful of values for R14 of less than 1k, as the opamp will be unable to supply the current needed to charge C5. R13 (3k) is easily made using a 1k2 and 1k8 resistor in series. C5 needs to be a low leakage capacitor - either a low leakage electrolytic or a tantalum. A standard electro is inappropriate for this circuit.

In addition, always keep R12 a minimum of 10 times R14 ... for example, if R14 were to be 1k, the minimum value for R12 will be 10k. This would be a very fast limiter indeed

READMORE...

Rangkain Pemutar CD/MP3 CD Dengan CDROOM

Pemutar CD/MP3 CD Dengan CDROOM

Most of the CDROMS available have an Audio-Out Output to either plug in the headphones or connect it to an amplifier. This circuit enables one to use the CDROM as a stand alone Audio CD player without the computer. This circuit is nothing but a power supply which supplies +5v, +12V and Ground to the CDROM drive and hence can be used without the computer. You should buy a D-type power connecter to connect this circuit's outputs to the CDROM.

Skema Rangkain Pemutar CD/MP3 CD Dengan CDROOM

Note:

• The circuit can be assembled on a Vero board
• Heat sinks are recommended for IC regulator 7812,7805
• Used transformator 12-CT-12 2 Ampere

The details of the D connector are shown along with the circuit diagram. Note that the D-connector goes into the CDROM in only one way and hence prevents any damage due to wrong connection. Ensure that the 12V(yellow) wire is connected to the right of the D-connector(as seen from behind ,i.e the connector holes away from you with the curved portion of the connector upwards) As soon as an Audio CD is inserted, the CD begins to play. To move to the next track, press the Skip-Track button on the CDROM front Panel.

READMORE...

Rangkaian Control Motor Stepper

Rangkaian Control Motor Stepper

The circuit is very simple and inexpensive. This is good thing because most commercial stepper motor controller ICs are quite expensive. This circuit is built from standard components and can easily be adapted to be controlled by a computer. If you use cheap surplus transistors and stepper motor, the price of the circuit can be kept to under $10.

Skema Rangkaian Control Motor Stepper

Note:
You should be able to substitute any standard (2N3055, etc.) power transistor for Q1-Q4.
Every time the STEP line is pulsed, the motor moves one step.
S1 changes the motors direction.

List Componet
R1, R2 ,R3, R4_____ 1K 1/4W Resistor
D1, D2, D3, D4_____ 1N4002 Silicon Diode
Q1, Q2, Q3, Q4_____TIP31 NPN Transistor (See Notes) TIP41, 2N3055
U1_____________4070 CMOS XOR Integrated Circuit
U2_____________ 4027 CMOS Flip-Flop
S1_____________ SPDT Switch
MISC 1 Case, Board, Wire, Stepper Motor


Pin & feature IC 4070 CMOS XOR I

Wide supply voltage range: 3.0V to 15V
High noise immunity: 0.45 VDD (typ.)
Low power TTL compatibility: Fan out of 2 driving 74L or 1 driving 74LS
Low power: 50 nW (typ.)
Medium speed operation: 12 MHz (typ.) with 10V supply



Pin & feature 4070 CMOS XOR

Wide supply voltage range 3.0V to 15V
High noise immunity 0.45 VDD typ.
Low power TTL Fan out of 2 driving 74L compatibility or 1 driving 74LS

READMORE...