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Wednesday, July 31, 2013

Electronicsalternative Energy Electronics Solar Wind Power

Solar Panel Wiring Diagram on Electronics   Alternative Energy Electronics Solar Wind Power
Electronics Alternative Energy Electronics Solar Wind Power.


Solar Panel Wiring Diagram on Solar Panel Diagrams
Solar Panel Diagrams.


Solar Panel Wiring Diagram on Water Heating Systems Collect The Sun S Energy Using Solar Panels To
Water Heating Systems Collect The Sun S Energy Using Solar Panels To.


Solar Panel Wiring Diagram on Solar Charge Controller   Solar Air Conditioner
Solar Charge Controller Solar Air Conditioner.


Solar Panel Wiring Diagram on Take A Look At The Diagram Above Since This Scenario
Take A Look At The Diagram Above Since This Scenario.


Solar Panel Wiring Diagram on Make A Small Solar Panel Home Wind Power Generator Solar Electricity
Make A Small Solar Panel Home Wind Power Generator Solar Electricity.


Solar Panel Wiring Diagram on Kyocera 130 Watt Solar Panel
Kyocera 130 Watt Solar Panel.


Solar Panel Wiring Diagram on Off Grid Solar Panel Wiring Guide For Maximum Power And Safe Wiring
Off Grid Solar Panel Wiring Guide For Maximum Power And Safe Wiring.


Solar Panel Wiring Diagram on Solar Panel Wiring Diagram   Solar Panels For Homes
Solar Panel Wiring Diagram Solar Panels For Homes.


Solar Panel Wiring Diagram on Solar Energy 8021 Wiring Diagram For Solar Panels
Solar Energy 8021 Wiring Diagram For Solar Panels.


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Tuesday, July 30, 2013

Current Driven Sallen Key Filter Circuit Diagram

Current-Driven Sallen Key Filter Circuit Diagram he low-pass Sallen-Key filter is staple for designers because it contains few components (A). By redesigning the filter, a current to voltage conversion can be avoided when the input signal to be filtered is in current form (B).

 Current-Driven Sallen Key Filter Circuit Diagram


Current-Driven Sallen Key Filter Circuit Diagram
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Monday, July 29, 2013

100W Guitar Power Amplifier Rise

The power amp board has remained unchanged since it was first published in 2002. It definitely is not broken, so there is no reason to fix it. The picture below shows a fully assembled board (obtainable as shown as M27). Using TIP35/36C transistors, the output stage is deliberately huge overkill. This ensures reliability under the most arduous stage conditions. No amplifier can be made immune from everything, but this does come close.

Guitar Power Amplifier Board

The power amp (like the earlier version) is loosely based on the 60 Watt amp historically in the past published (Project 03), but its increased gain to match the preamp. Other modifications include the short circuit protection - the tiny groups of parts next to the bias diodes (D2 and D3). This new version is not massively different from the original, but has adjustable bias, and is designed to provide a "constant current" (i.e. high impedance) output to the speakers - this is achieved using R23 and R26. Note that with this arrangement, the gain will change depending on the load impedance, with lower impedance giving lower power amp gain. This is not a controversy, so may safely be ignored.

Ought to the output be shorted, the constant current output characteristic will provide an preliminary level of protection, but is not foolproof. The short circuit protection will limit the output current to a comparatively safe level, but a sustained short will cause the output transistors to fail if the amp is driven hard. The protection is designed not to operate under normal conditions, but will limit the peak output current to about 8.5 Amps. Under these conditions, the internal fuses (or the output transistors) will probably blow if the short is not detected in time.

Figure 2 - Power Amplifier

Figure two shows the power amp PCB parts - except for R26 which doesnt mount on the board. See Figure 1B to see where this ought to be physically mounted. The bias current is adjustable, & ought to be set for about 25mA dormant current (more on this later). The recommendation for power transistors has been changed to higher power devices. This will give improved reliability under sustained heavy usage.

As shown, the power transistors will have an simple time driving any load down to four ohms. In case you dont use the PCB (or are happy to mount power transistors off the board), you can use TO3 transistors for the output stage. MJ15003/4 transistors are high power, & will run cooler because of the TO-3 casing (lower thermal resistance). Watch out for counterfeits though! Theres plenty of other high power transistors that can be used, & the amp is tolerant of substitutes (as long as their ratings are at least equal to the devices shown). The PCB can accommodate Toshiba or Motorola 150W flat-pack power transistors with relative ease - in case you desired to go that way. TIP3055/2966 or MJE3055/2955 may even be used for light or ordinary duty.

At the input finish (as shown in Figure 1B), there is provision for an auxiliary output, & an input. The latter is switched by the jack, so you can use the "Out" & "In" connections for an outside effects unit. Alternatively, the input jack can be used to connect an outside preamp to the power amp, disconnecting the preamp.

The speaker connections permit up to 8 Ohm speaker cabinets (giving four Ohms). Do not use less than four ohm lots on this amplifier - it is not designed for it, & wont give reliable service!

All the low value (i.e. 0.1 & 0.22 ohm) resistors must be rated at 5W. The 0.22 ohm resistors will get warm, so mount them away from other parts. Needless to say, I recommend using the PCB, as this has been designed for optimum performance, and the amp gives an excellent account of itself. So nice in fact, that it may even be used as a hi-fi amp, and it sounds excellent. In case you were to make use of the amp for hi-fi, the bias current ought to be increased to 50mA. Ideally, you would use better (faster / more linear) output transistors as well, but even with those specified the amp performs well indeed. This is largely because they are run at comparatively low power, and the extreme non-linearity effects would expect with only transistors do not occur because of the parallel output stage.

Make positive that the bias transistor is attached to of the drivers (the PCB is laid out to make this simple to do). A some quantity of heat sink compound as well as a cable tie will do the job well. The diodes are there to protect the amp from catastrophic failure ought to the bias servo be incorrectly wired (or set for maximum current). All diodes ought to be 1N4001 (or 1N400? - anything in the 1N400x range is fine). A heat sink is not needed for any of the driver transistors.

The life of a guitar amp is a hard, and I recommend that you use the largest heat sink you can afford, since it is common to have elevated temperatures on stage (chiefly due to all the lighting), and this reduces the safety margin that normally applies for domestic equipment. The heat sink ought to be rated at 0.5° C/Watt to permit for worst case long term operation at up to 40°C (this is not unusual on stage).

Make sure that the speaker connectors are isolated from the chassis, to keep the integrity of the earth isolation parts in the power supply, & to make sure that the high impedance output is maintained.
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Sunday, July 28, 2013

0V to 50 Volt Variable Regulator circuits

this Regulator circuits is
very simple variable power supply circuit can be made using this electronic circuit diagram .This variable regulator circuit will provide an variable regulated output voltage , between 0 and 50 volts . The CA3140 operational amplifier compares the regulator output to a reference voltage , that depends on the R9 value.

The output voltage will be nominally twice the voltage between the positive input ( noninverting ) of the CA3140 and ground . The unregulated input voltage must be around 60 volts The output voltage can be set between 0 an 50 volts using R9 potentiometer .The 2N3055 transistors must be mounted on a heatsink , to prevent the overheating of transistors .
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Friday, July 12, 2013

PWM Generator Schematic

PWM waveforms are commonly used to control the speed of DC motors. The mark /space ratio of the digital wave-form can be defined either by using an adjustable analogue voltage level (in the case of a NE555 based PWM generator) or digitally using binary values. Digitally derived PWM waveforms are most often produced by the timer/counter modules in microcontrollers but if you do not want to include a microcontroller in your circuit it’s also quite simple to generate the signals using discrete logic components. An extension of the circuit shown can pro-duce two PWM waveforms from an 8-bit digital input word. Each signal has 15 val-ues. The 8-bit word can be produced for example from an expansion board fitted in a PC or from an 8-bit port of a processor which does not have built-in PWM capability or from a laptop’s printer port. 
Discrete PWM Generator Circuit Diagram
Discrete PWM Generator


The mark/space ratio is only programmable up to 15/16 rather than 16/16; a binary input of 0000 produces a continuous low on both outputs turning both motors off. Similar circuits often employ a dedicated ‘enable’ input to turn the motors off but it is not necessary in this design.

The diagram shows the circuitry required to produce just one waveform. For the full two channel circuit it is necessary to use an additional 74HC193. The clock signal produced by the HCF4060 generator can be used to drive both channels and the free flip flop in the 74HC74 package can be used for the second channel (the corresponding pin numbers are shown in brackets). Alto-gether the entire two channel circuit can be built using just four ICs. Link
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Thursday, July 11, 2013

Sound Activated Lights

This diy sound activated lights circuit turns a lamp ON for a short duration when the dog barks (or a relatively strong sound) giving an impression that the occupants have been alerted. The condenser microphone fitted in a place to monitor sound and generates AC signals, which pass through DC blocking capacitor C1 to the base of transistor BC549 (T1). Transistor T1 along with transistor T2 amplifies the sound signals and provides current pulses from the collector of T2. When sound is produced in front of the condenser mic, triac1 (BT136) fires, activates lights and the bulb (B1) glows for about two minutes.
 
 
Assemble the sound activated lights circuit on a general purpose PCB (circuit board) and enclose in a plastic cabinet. Power to the sound activated switch circuit can be derived from a 12V, 500mA step-down transformer with rectifier and smoothing capacitor. Solder the triac ensuring sufficient spacing between the pins to avoid short circuit. Fix the unit in the dog’s cage or close to the sound monitoring spot, with the lamp inside or outside as desired. Connect the microphone to the sount activated lights circuit using a short length of shielded wire. Enclose the microphone in a tube to increase its sensitivity.

Caution. Since the sound activated lights uses 230V AC, many of its points are at AC mains voltage. It could give you lethal shock if you are not careful. So if you don’t know much about working with line voltages, do not attempt to construct this circuit. We will not be responsible for any kind of resulting loss or damage.
 
 
 
 
 
 
 
Source by : Streampowers
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Wednesday, July 10, 2013

Signal Tracer and Injector

A simple test circuit to fault find audio and radio equipment. Can be used to inject a square wave signal, rich in harmonics, or used with headphones as an audio tracer.

Signal Tracer and Injector Schematic


Notes:
A single pole double throw sitch is used to switch between inject and trace modes. The diagram is drawn in trace mode, the earpiece being connected to the collector of the last transistor. Both transistors are wired as emitter followers, providing high gain. DC blocking is provided by the 1n capacitor at the probe end, and the two stages are capacitively coupled.

when the switch is thrown the opposite way (to the blue dot) both transistors are wired as an astable square wave generator. This provides enough harmonics from audio up to several hundred kilohertz and is useful for testing AM radio Receivers.
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Tuesday, July 9, 2013

Lithium ion Charger Using MAX8844

Using the MAX8844 lithium ion charger IC released by Maxim Semiconductors you can design an very simple and efficiency charger circuit for charging a single cell lithium-ion battery . The MAX8844 lithium ion charger integrate a current-sense circuit, MOSFET pass element, thermal-regulation circuitry, and eliminate the external reverse-blocking Schottky diode to create the simplest and smallest charging solutions for handheld equipment.

Lithium ion Charger Circuit diagram


Also , using this charger solution the power source is optimized by the MAX8844Z using automatically select function between the USB or IN power source but if are both power sources connected the highest priority is for IN power source to ensure the shortest charging time for the system . The MAX8844 charger chip accept an input voltages range from 4.25V to 28V (IN and USB), but the charging is disabled if the input voltage exceeds +7.5V for protection against unqualified or faulty AC adapters.

These charger IC is very easy to be implemented in applications like : Bluetooth Equipment , Cellular and Cordless Phones Charging Cradles and Docks, Digital Still Cameras , MP3 Players Smart Phones and PDAs , USB Appliances . The maximum charging current is programmed by an external resistor connected from SETI to GND (RSETI). Use the following equation to determine the fast-charge current (IFAST-CHARGE): FAST CHARGE= 1250V/RSETI, where IFAST-CHARGE is in amps and RSETI is in ohms. RSETI must always be 1.25k or higher due to the continuous charging current limit of 1ARMS.

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Monday, July 8, 2013

4 Minute Shower Timer

Gone are the days when we can afford to luxuriate under a hot shower for hours on end. Well, maybe the showers weren’t quite that long but most people are used to taking showers in the tens of minutes. It’s easy to lose track of time in the shower. And it does feel nice.

That’s a luxury that’s no longer economically nor ecologically sustainable. First of all, we’re short of water. In most areas of Australia the powers-that-be keep telling us if we don’t be good boys and girls and cut our water usage then we are going to run out.

(Those same powers [read politicians] that keep blaming us wasteful consumers don’t mention that for the most part water shortages are their fault, because they haven’t invested the necessary dollars in water infrastructure while population has steadily increased for much of the last half century. But let’s not get into that argument. At least not right now . . .)

Second, we’re short of electric power. The power that goes to heat the water is also in very short supply. Load shedding (ie, blackouts!) is becoming more and more common as supply authorities attempt to cut peak loads. Those same powers-that-be keep telling us that if we don’t reduce our consumption of power, it’s going to get worse. (Those same powers [read politicians] that keep blaming us wasteful consumers, etc etc etc . . .)

Putting aside all the scare-mongering that’s going on in political circles (my spell checker wanted to change that to circuses, which would be perhaps more apt) it really does make sense for us, as consumers, to try to save both water and power – if only because that means less of our hard-earned dollars will end up in Government coffers.

One way to do both, of course, is to take shorter showers. How short?

The 4-minute shower

Believe it or not, it is entirely possible to take a shower in four minutes – including, if you need to, washing your hair. In fact, without shampooing, a sub-three-minute shower is perfectly practical. People in the bush who don’t have the luxury of hot water have been "getting" that sort of shower for years: get in, get wet, get clean, get out!

Let’s face it – all you really need to do is get wet, soap up and rinse off. Get wet: 30 seconds. Soap up: 60 seconds. Rinse off: 60 seconds. That’s two and a half minutes. Add another 60 seconds to shampoo your hair and there’s your four minute shower – with 30 seconds left over for good measure.

OK, if you agree that four minutes is enough time, how do you go about convincing everyone in your family?

4-minute-shower-timer-circuits-diagrams 1

The ST4 Shower Timer

This rather ingenious (and patented) design is completely automatic, turning on about 20-30 seconds after it "hears" the first "sssshhh" of the shower – giving you enough time to adjust the water temperature – then beeping each minute up to the magic four minutes, at which time it sounds an alarm.

The alarm stops when you turn the shower off. But if you try to fool it by turning the shower off for a moment and then back on again, the alarm will start back up again. It resets after about a minute of no-shower-sound, ready for the next person to take their shower.

Part of the secret to this circuit is the use of the piezo buzzer: it is not only sounds the beep/alarm, as you would expect but it is also used as a "microphone" to pick up the splash sound.

There’s no on-off switch; it simply operates when it hears the shower turn on (listening for the distinctive splashing sounds of the water). There is an internal 3-position switch and preset pot which are adjusted to give the desired sensitivity – once set, you can forget it.

There are also pots to control clock frequency and tone of alarm – but these are set in the factory and should not need touching.

It’s operated by a 9V battery (alkaline preferred) which should last for at least 12 months. Current drain, when ready to operate but inactive, is comparable to that of a smoke detector – around 10-15mA.

The circuit, including the piezo, is housed on a single PC board which fits (along with the 9V battery) into a purpose-designed two-part case. When correctly assembled is quite waterproof. Mounted on the shower wall it allows shower sound to enter and beeps/alarm to escape without the circuit getting at all damp.

The case, as we said, is in two parts. These snap together to form a nice, tight seal around the PC board, with alignment of the two parts taken care of by pins and holes which mate. Each half of the case is fitted with a suction cap which allows the unit to mount to any smooth shower wall (or even a glass screen).

While the ST4 Shower Timer is available fully built and tested, we are more interested in it as a kit which you assemble yourself. Even here, most of the hard work – soldering the surface-mount components and ICs – is already done for you. In fact, as supplied, the PC board is built and tested, ready for you to put together

Putting it together

Assembly is as simple as removing the backing and the centre from the self-adhesive "donut" foam ring and sticking it, as central as possible, onto the piezo transducer. Then similarly stick the rectangular foam pad onto the back of the PC board (it keeps the battery snug while preventing it shorting to or across the board), then push the PC board into the bottom half of the case.
4-minute-shower-timer-circuits-diagrams1

The bottom half can be identified by the slots for the transducer. When the board is pushed fully home, the foam donut "gasket" provides a seal in a moulded housing inside the case, preventing any water entering the case – theoretically even if dunked.

We say theoretically because it is designed that way – but commonsense would suggest you don’t try to prove it. Because the transducer slots are at the bottom of the case, spray would have to be travelling upwards to enter – possible, of course.

But the foam donut stops this water going any further. While the transducer itself is not sealed, its internal construction means that it is also an effective water barrier, so with the sealing donut in place, spray cannot enter the case nor either around or through the transducer.

All this means that the shower timer is for all intents and purposes waterproof, especially from spray. Once the PC board has been pushed home, the battery can be connected and slid down into the case, alongside the (now insulated) back of the PC board. It should be a relatively snug fit.

In the unlikely event that the suction caps have come off the case halves in transit, simply slide them back into their respective slots on each end – the photos show where they go. Slide the two halves of the case together, ensuring that the channels which hold the suction caps line up exactly – the pins in one half won’t mate if they don’t. The two case halves should "snap" together and that completes construction.

Testing

If you don’t want to get wet, you can use a small unmuted FM radio, off-station, to simulate the sound of a shower. (If your FM radio mutes automatically, or the mute cannot be turned off, this option won’t work. You’ll need to check it in situ – in the shower!) The FM radio will produce predominantly white noise, which is fairly close to the sound of a shower stream striking the bottom of the shower or bath.

Turn the radio on and the timer should give a chirping sound after 20-30 seconds (that’s the water temperature adjustment period). Then it should beep after each minute from there, with a series of beeps (7.5 seconds on, 7.5 seconds off) at the end of four minutes. Turn the radio off and the timer should reset.

Mounting in the shower

The timer always mounts vertically, with the piezo transducer towards the bottom. The suction caps should stick very well to any ceramic tile, glass or other smooth surface – if necessary, give ’em a lick first! Best position for the timer is about 300-400mm from the floor but it should work reasonably well up to about waist height.

If you need to mount the unit higher than this, or if it doesn’t appear to be sensitive enough, open it up and slide the switch up one notch. Don’t mount any higher than necessary. In some very low volume showers, (eg some gravity feeds), you might need to adjust the sensitivity right up but this would normally be unlikely.

You should not need to adjust any of the pots – they are preset on factory assembly. Once mounted, give it another run, this time with the shower. It should perform in the same way as it did in your "white noise" test.

The only time you should need to remove the unit from the wall is to replace the battery and this could be up to a couple of years or so! Don’t pull on the timer to remove it, slide a knife or some other thin, flat object under the suction caps to break the seal.

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Sunday, July 7, 2013

50W audio amplifier LM3876

LM3876 is a high performance audio power amplifier IC from National Semiconductors. The LM3876 can deliver 50watts of output power into an 8 ohm loudspeaker. LM3876 has excellent signal to noise ratio and has wide supply voltage range. Other features of LM3876 are output to ground short circuit protection, input mute function, and output over voltage protection, etc. Applications of LM3876 are component stereo, compact stereo, surround systems, self powered speakers, etc.
Circuit diagram :
50-w-audio-amplifer-circuit diagram
50W audio amplifier Circuit Diagram
The 50 watt audio amplifier  circuit shown below is designed based on the application diagram from the data sheet of LM3876. Some modifications are made on the original circuit for improving the performance. The bipolar electrolytic capacitor C7 is the input DC decoupling capacitor. R4 is the input resistance. R2 & R1 and bipolar electrolytic capacitor C5 forms a feedback circuit. C2, C1 are filter/by-pass capacitors for the positive supply rail. C4 & C3 are the filters/by-pass capacitors for the negative supply rail. The feedback resistor R2 sets the gain of the amplifier. L1 provides high impedance at high frequencies so that R7 may decouple capacitive loads. R3 is the mute resistance which allows 0.5mA to be drawn from pin8 to turn the mute function OFF. S1 is the mute switch. Resistor R6 and capacitor C8 forms a Zobel network which improves the high frequency stability of the amplifier and prevents oscillations.
Notes :
  • The LM3876 can be operated from a supply voltage range of +/-12V to +/-49V DC.
  • I recommend +/-35V DC for powering the IC.
  • LM3876 requires a proper heat sink.
  • Quiescent current of LM3876 is around 70mA

Streampowers
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Saturday, July 6, 2013

Gu10 LED Light Bulbs Driver Schematic

A very simple high efficiency Gu10 led light bulbs driver power supply circuit that can be used as a LED driver for GU10 lamp can be designed using this schematic circuit.This high efficiency Gu10 led light bulbs LED driver is designed to drive 12 V at 0.3 A from an input voltage range of 90 VAC to 265 VAC using few external components.

This Gu10 led light bulbs driver power supply uses the LNK605DG IC from the LinkSwitch-II family by Power Integrations. The LNK605DG provides a sophisticated range of protection features including auto restart for open control loop and output short-circuit conditions. As you can see in the circuit diagram , this LED driver require few external electronic components .The LNK605DG Ic from LinkSwitch-II family is an integrated controller plus 700 V power MOSFET intended for use in LED driver or charger applications.

Gu10 LED Light Bulbs Driver Circuit Diagram


Gu10 LED Light Bulbs Driver Electronic

The rectified and filtered input voltage is applied to one end of the primary inding of T1 transformer and the other side of the transformer’s primary winding is driven by the integrated 700 V power MOSFET in U1. The leakage inductance drain voltage spike is limited by an RCDR clamp consisting of D1, R3, R4, and C3.

The secondary of the transformer is rectified by D3 ( a Schottky barrier type was selected for higher efficiency) and filtered by C7. Resistor R1 and C6 dampen high frequency ringing and reduce the diode voltage stress The T1 transformer must have 30 turns from NC to pin1( with 0.221 mm copper wire) , 80 turns from pin1 to pin 2 ( with 0.15 mm copper wire) , 15 turns from pin7 to pin8 ( with 0.4mm copper wire) and 16 turns from pin A to pin B (using 0.2mm copper wire ) .
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Friday, July 5, 2013

Mini Metronome

Linear scale-Small size 40 to 208 beats per minute


Mini Metronome Circuit diagram:
 

Notes:
  • Q1 & Q2 provide linear frequency operation of IC1 following P1 resistance variation.
  • Q3 was added in order to obtain a louder click, similar to clockwork metronomes.
  • 12V micro battery was used to obtain more output power and more compactness.
  • Rotate P1 fully towards R2, then set R1 to obtain 40 beats per minute (compare with another metronome).
  • Rotate P1 fully towards R3, then set R4 to obtain 208 beats per minute.
  • Finally mark the entire scale with the usual metronome steps as following:
  • 40 - 42 - 44 - 46 - 48 - 50 - 52 - 54 - 58 - 60 - 63 - 66 - 69 - 72 - 76 - 80 - 84 - 88 - 92 - 96 - 100 - 104 - 108 - 112 - 116 - 120 - 126 - 132 - 138 - 144 - 152 - 160 - 168 - 176 - 184 - 192 - 200 - 208.

Parts:

P1______100K   Linear Potentiometer
R1_______10K   1/2W Trimmer Cermet
R2_______10K   1/4W Resistor
R3______330K   1/4W Resistor
R4_______50K   1/2W Trimmer Cermet
R5______100K   1/4W Resistor
R6,R7_____1K   1/4W Resistor
C1________1µF   63V Polyester Capacitor
C2_______10nF   63V Polyester Capacitor
C3_______47µF   25V Electrolytic Capacitor
IC1_____NE555   General purpose timer IC
Q1,Q2___BC560   45V 100mA Low noise High gain PNP Transistors
Q3_____ZTX753   100V 2A PNP Transistor
SW1______SPST Switch (Ganged with P1)
SPK______8 Ohm 40mm. Loudspeaker
B1_____12V Battery (MN21, GP23A or VR22 type)
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Thursday, July 4, 2013

10 to 14W Class A Audio Amplifier

I have built this amplifier and it does sound good. It requires a preamp as it hasnt got much gain. It requires big heat sinks and a large transformer and a great power supply and careful wiring, but in the end it is xtremely simple and it sounds very good. The zener diode rejects any ripple coming from the power supply, But you still only want a ripple of 10mV max. The ripple reaching the input is amplified, so the zener diode gets rid of that, but whatever ripple there is will still reach the power stage.

10 to 14W Class A Audio Amplifier
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Wednesday, July 3, 2013

Tri Waveform Generator

The Tri-Waveform Generator can be used for a number of different uses. The one that I use it for is a signal generator to test circuits. The frequency range is 20 to 20khz. and can be adjusted by R1. The duty cycle or the time that the waveform is high and the time that the waveform is low can be adjusted by R4. The purpose of R2 and R3 are to clean up any distortion on the sine wave output. To do this you must hook up the sine wave output to and oscilloscope and adjust R2 & R3 to make the sine wave as accurate as possible.

Tri-Waveform Generator Circuit Diagram

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