Showing posts with label Amp. Show all posts
Showing posts with label Amp. Show all posts
Thursday, October 23, 2014
Subwoofer Pre Amp Filter
Acoustic spectrum is extended by the 20Hz frequency is very low and reaches as high frequency 20000Hz. In the low frequency is lowered sense of direction. This reasoning leads us to attribute to the speakers use of very low frequency. Making it to you we propose to distinguish these frequencies, in order for him to lead us on a suitable amplifier.
Acoustic filter are met at different points in the sound system. Applications knownest they are filter baxandal to organize low-and high-frequency tones and crossover filter where the acoustics are separated in the subareas, for it leads to the appropriate speakers. Applications that you can we propose is a simple filter that limits the acoustic region (20-20000Hz) in 20-100Hz region.
With manufacturing, we propose that you can you can make an active filter for you lead a very low frequency loudspeaker. With this you will put a big one between speaker HIFI speakers from you. In order for you to have a complete picture of sound you will need also an appropriate amplifier. In the entry of circuit you will connect the two roads out of the preamplifier or the exit of the preamplifier few.
The series production in order to allocate out of the facility led a series of subwoofer power. If for some reason you do not have space for you to put the third speaker in the courtroom, then you can choose a smaller speaker. This output will depend on the type of music that you hear. If in deed you have the space, then after you create a filter and still say thank you, you can he recommend your friends or still makes each other to your friends.
Circuit diagram ![]() |
Filter | PreAmp Subwoofer circuit diagram |
Parts
R1 = 39 Kohm , R2 = 39 Kohm,R3 = 47 Kohm,R4 = 10 Ohm,R5 = 22 Kohm,R6 = 4.7 Kohm,R7 = 22 Kohm, R8 = 4.7 Kohm, R9 = 10 Ohm, R10 = 220 Ohm, C1 = 39 pF,C2 = 0.1 UF,C3 = 0.1 UF, C4 = 0.2 UF, C5 = 0.4 UF, C6 = 0.1, UF C7 = 0.1 UF, IC1 = TL064
In the form that appears theoretical filter circuit. At first glance we see three different circuits which are mainly produced by two rounds of operational amplifiers. This circuit is a mixture, with the assistance variable amplifier and variable filters. Late-making requires a series of operations catering catering with the same trend with  ± 12. operational amplifier which is the active element for this circuit is the type of dual operation as a TL082 and NE5532.
The operational amplifier is included in a family is equipped with field-effect transistor IFET in their entries. Each member is allocated a family in bipolar transistor circuits and field effect. This circuit can function in a high inclination, because of their high propensity to use transistors. Also they have the high honor rhythm elevation (slew rate), low polarization at this time for entry and little influenced by temperature. The operational amplifier has an area of 3MHz unity gain bandwidth. Another important element for them is a great choice reject noise, there are currently in the line of catering.
Price refused to greater than 80dB, their consumption is small, from 11 to 3 mA. They briefly sold internally with eight pins and allocate two operational amplifiers, In the same row 14 pin in short they combine four operations, the trade them for sale with code TL074, TL084 and TL064, a nutshell with eight pins they sold the operational amplifier TL071 TL061 kajTL081 . In manufacturing we use the TL082 that has two operational. First operation of TL082 he worked as an amplifier and mixed with two channels, the entry is negative, it is a little mixed with the two resistances. A potentiometer on the steps of determining the aid circuit. At this point the left wing and right-channel preamplifier they added means of two resistances. En operational continuity with the help strengthen the signal is made depending on the price that has been potentiometer.
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PCB layout |
Place runner comparable with the assistance of the circuit. The second operational amplifier is a filter manufacturing. Filters from the acoustic frequency from second grade and he made a round of operational amplifiers. This filter section with variable frequency low-cut. This frequency can be changed and took the price of very low frequency of 30Hz or still exceeds 150Hz. The frequency of the filter depends on the price cuts that have circuit elements. Change the value of the elements that we can have a frequency cut 150Iz, 130Hz, 100Hz, 7A? Z, 6A? Z even 3A? Z, is the price that they can be achieved by simple rotation of the double potentiometer. Filter circuit has been made about an operation that has completed a TL082 dual operational amplifier. In the filter out we will connect the plug load which is connected amplifier. In a series of exit are presented, which are limited as to the extent of frequency, the signal applied in the entry of the circuit.
Wednesday, October 15, 2014
Build a 10 Amp 13 8 Volt Power Supply Circuit Diagram
Sometimes amateurs like to home-brew their power supplies instead of purchasing one off the shelf at any of the major ham radio retail dealers. The advantage to rolling your own power supply is that it teaches us how they work and makes it easier to troubleshoot and repair other power supply units in the shack. It should be noted that there is no real cost advantage to building your own power supply unless you can get a large power transformer and heat sink for a super low price.
Of course rolling our own gives us the ability to customize the circuit and make it even more reliable than commercial units. The circuit in Figure 1 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 commercial units have. Just like other commercial units, this circuit uses the LM723 IC which gives us excellent voltage regulation. The circuit uses 3 pass transistors which must be heat sinked. Resistor R9 allows the fine tuning of the voltage to exactly 13.8 volts and the resistor network formed by resistors R4 through R7 controls the current limiting.
The LM723 limits the current when the voltage drop across R5 approaches .7 volts. To reduce costs, most commercial units rely on the HFE of the pass transistors to determine the current limiting. The fault in that system is that the HFE of the pass transistors actually increases when the transistors heat up and risks a thermal runaway condition causing a possible failure of the pass transistors. Because this circuit samples the collector current of the pass transistors, thermal runaway is not a problem in this circuit making it a much more reliable power supply.
The only adjustment required is setting R9 to the desired output voltage of anywhere between 10 and 14 volts. You may use a front panel mounted 1K potentiometer for this purpose if desired. Resistor R1 only enhances temperature stability and can be eliminated if desired by connecting pins 5 and 6 of IC-1 together. Although it really isn’t needed due to the type of current limiting circuit used, over voltage protection can be added to the circuit by connecting the circuit of Figure 2 to Vout. The only way over voltage could occur is if transistors Q2 or Q3 were to fail with a collector to emitter short. Although collector to emitter shorts do happen, it is more much more likely that the transistors will open up when they fail.
10 Amp 13.8 Volt Power Supply Circuit Diagram
I actually tested this and purposely destroyed several 2N3055’s by shorting the emitters to ground. In all cases the transistors opened up and no collector to emitter short occurred in any transistor. In any event, the optional circuit in Figure 2 will give you that extra peace of mind when a very expensive radio is used with the power supply. The circuit in Figure 2 senses when the voltage exceeds 15 volts and causes the zener diode to conduct. When the zener diode conducts, the gate of the SCR is turned on and causes the SCR to short which blows the 15 amp fuse and shuts off the output voltage.
A 2N6399 (Tech America) was used for the SCR in the prototype but any suitable SCR can be used. While over voltage protection is a good idea, it should not be considered a substitute for large heat sinks. I personally feel the best protection from over voltage is the use of large heat sinks and a reliable current limiting circuit. Be sure to use large heat sinks along with heat sink grease for the 2N3055 transistors. I have used this power supply in my shack for several months on all kinds of transceivers from HF, VHF to UHF with excellent results and absolutely no hum. This power supply will be a welcome addition to your shack and will greatly enhance your knowledge of power supplies.
Parts
R1 1.5K ¼ Watt Resistor (optional, tie pins 6 & 5 of IC1 together if not used.)
R2,R3 0.1 Ohm 10 Watt Resistor (Tech America 900-1002)
R4 270 Ohm ¼ Watt Resistor
R5 680 Ohm ¼ Watt Resistor
R6,R7 0.15 Ohm 10 Watt Resistor (Tech America 900-1006)
R8 2.7K ¼ Watt Resistor
R9 1K Trimmer Potentiometer (RS271-280)
R10 3.3K ¼ Watt Resistor
C1,C2,C3,C4 4700 Microfarad Electrolytic Capacitor 35 Volt (observe polarity)
C5 100 Picofarad Ceramic Disk Capacitor
C6 1000 Microfarad Electrolytic Capacitor 25 Volt (observe polarity)
IC1 LM723 (RS276-1740) Voltage Regulator IC. Socket is recommended.
Q1 TIP3055T (RS276-2020) NPN Transistor (TO-220 Heat Sink Required)
Q2,Q3 2N3055 (RS276-2041) NPN Transistor (Large TO-3 Heat Sink Required)
S1 Any SPST Toggle Switch
F1 3 Amp Fast Blow Fuse
D1-D4 Full Wave Bridge Rectifier (RS276-1185)
T1 18 Volt, 10 Amp Transformer Hammond #165S18 (Tech America 900-5825)
R1 1.5K ¼ Watt Resistor (optional, tie pins 6 & 5 of IC1 together if not used.)
R2,R3 0.1 Ohm 10 Watt Resistor (Tech America 900-1002)
R4 270 Ohm ¼ Watt Resistor
R5 680 Ohm ¼ Watt Resistor
R6,R7 0.15 Ohm 10 Watt Resistor (Tech America 900-1006)
R8 2.7K ¼ Watt Resistor
R9 1K Trimmer Potentiometer (RS271-280)
R10 3.3K ¼ Watt Resistor
C1,C2,C3,C4 4700 Microfarad Electrolytic Capacitor 35 Volt (observe polarity)
C5 100 Picofarad Ceramic Disk Capacitor
C6 1000 Microfarad Electrolytic Capacitor 25 Volt (observe polarity)
IC1 LM723 (RS276-1740) Voltage Regulator IC. Socket is recommended.
Q1 TIP3055T (RS276-2020) NPN Transistor (TO-220 Heat Sink Required)
Q2,Q3 2N3055 (RS276-2041) NPN Transistor (Large TO-3 Heat Sink Required)
S1 Any SPST Toggle Switch
F1 3 Amp Fast Blow Fuse
D1-D4 Full Wave Bridge Rectifier (RS276-1185)
T1 18 Volt, 10 Amp Transformer Hammond #165S18 (Tech America 900-5825)
Sunday, October 5, 2014
9 Volt 2 Amp PSU Single IC Regulator Power Supply
Notes
There is little to be said about this circuit. All the assignment is done by the regulator. The 78S09 can bear up to 2 amps connected achievement whilst advancement a low babble and actual able-bodied adapted supply.
The ambit will assignment after the added components, but for about-face polarity aegis a 1N5400 diode is provided at the input, added cutting actuality provided by C1. The achievement date includes C2 for added filtering, if powering a argumentation ambit than a 100nF capacitor is additionally adorable to abolish any aerial abundance switching noise.
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