Solid State Relays Circuit

Welcome to Free circuit dot com ,today we have classic circuit to implement solid state relay in your electronic project .

Solid state relays are almost everywhere these days, but they are very expensive. So, your efforts to build their own salary. Especially since it’s only a few parts and circuit simple and straightforward. Solid state relay is not really at all relays. There are no “relay” is available only with electronics, connection works. It works well as a relay, you can use low voltage higher and better. “Relay” between 115/220V AC wires in place, although it was customary, the neutral conductor and leave unchanged phases and neutral.

As long as no voltage (left in picture), the phototransistor TIL111 blocks of energy, and thus is not available. To ensure that the base TIL111 is fed to the transmitter (s) through the 1M resistor. This method prevents the base of transistor BC547B will be low and remains biased ‘on’. Collector is low and the gate (g) TIC106M thyristor, which is still in the country, “off”. 4-diode bridge rectifier circuit has no power apart from a small base and collector current BC547B, which is not enough to turn over the 330-ohm resistor TIC226M triac. Current “Load”, is very small.

With an input voltage, say 5 volts, the diode in the TIL111 lights up and activates the phototransistor. The voltage drop 1MEG ohm resistor in series with 22K resistance increases demand, which block the BC547B transistor. Collector current of the fact that the AC voltage falls below a certain value, which is VA. This ensures a sufficiently large voltage drop across the resistor 330 ohms triac switches ‘on’. The voltage on triac is currently only a few volts, so that practically the whole 115/220 AC voltage on the “Upload”.

The triac is a 100nF capacitor and impedance of 47 ohms, 100nF capacitor for the 330 ohm resistor is to protect the triac to be undesirable distortions caused by small peaks. To create the possibility of this circuit with different voltages to be switched, added BF256A FET. The FET acts as a current source from the source (s) with a gate (g). This means that this FET determines the current TIL111, regardless of the input voltage (up to a certain tolerance, of course). 1N4148 diode is to protect the circuit from reverse polarity.
(Tony: TIL111 is a so-called “optical coupling” with NPN output and can be replaced with NTE3042)

Good point line, as is the separation of AC and DC voltage, so this circuit is used in many applications, about 1.5 kW, when the triac is mounted on the large size of the cooling fins.
“M” appears Triac means it’s 600volt type, “D” for 400V. So be sure to go to the M-type.

NTE replacement for this circuit are 600volt types which are more than sufficient for our 110/115VAC. Even if you decide to print for this circuit is enough space between the lines AC and non AC these tracks to be close.

preamp power supply

This is IRRESPONSIBLE and DANGEROUS!!

Welcome back to Free circuit dot com again,today i would like to present the preamp power supply circuit.

this circuit is small and easy to assembly,we will use IC regulator 7915 and 7815 for main control voltage.

About all capacitors are filter noise and frequency.

We will take diodes to allow an electric current to pass in one direction (called the diode’s forward direction), while blocking current in the opposite direction

100W amp MOSFET Print Layout

This week we had the same issue of For today, I bring the audio amplifier circuit 100w Mosfet IRFP250N same number.
But I have no schematic to PCB and accessories print layout of a PCB, which can be used immediately.
For a list of devices. I have already mentioned in accessories print layout.
You can supply them all.
The power supply 50Vdc.

We have the PCB thus as picture below.

100W MOSFET PCB

protection output of amplifiers

The short circuit proof outputs of amplifiers and speakers, throw some interesting elements, such as the isolation of the speakers from the exit of the amplifier, when is a constant tension presented abandoned or if the heatsink temperature rises excessively, the simultaneous and delayed connecting speakers to the amplifier so until we stop them, the familiar sounds of the charge – discharge of capacitors of the supply.

It ¡s is formed by a binary comparator [IC 1], the transistors Q1-2 and preliminary LED D5-6. The supply of the circuit can have a positive stress [point A], especially the food that is on the D3 and R17, the 15V + stabilized.

Electronic Part List

R1-2=27 Kohms
R3=1.4 Kohms  
R4=1 Mohms  
R5-14-17=3.3 Kohms  
R6-7=100 Kohms  
R8=47 Kohms   
R9-11=120 Kohms  
R10=470 Kohms  
R12=15 Kohms  
R13=1.5 Kohms
R15=4.7 Kohms
R16=33 Kohms
R18=1.5 Kohms 5W
C1-2=100uF 63V
C3=470nF 100V MKT
C4-5=47uF 25V
Q1-2-3=BC337
Q4=BC639
D1=1N4148
D2=1N4004
D3=15V 1.5W Zener
D4=1N4002
D5-6=LED
RL1=24V Relay 
RTH=KTY81-122
IC1=LM393

Point B is one of the secondary coil of the main AC-connected transformer. When the power switch of the AC main line, then an AC voltage (secondary coil of the transformer), is shown in section B, is it? D2 from the negative voltage is recovered and deliver them by R9, cut the Q3 of this year and start charging the C4-R10-11. As long as the last time that the charge on the capacitor, the input [+] IC2B comparator is found in small amounts in proportion to the power [-]. The output of IC2B has a low level, so Q4 will remain in the Cutt off and stay ahead of the RL1, which he D6. Only the C4 is charged, the situation changes in the IC1B, RL1 is activated, the speakers to the output of the amplifier, the D6 it out. If it’s interrupted, the process is reversed, and the speaker without breaking pass interference.

If the circuit during the work, the problem of continuing tensions in the output of the amplifier presented in the RL1 and protects the speaker. This is done using the Q1-2. The acoustic signal from the amplifier output, led to point D, the alternative tensions led to the bottom of the C1-2, which is a non-polar capacitor. Continuous voltage that is greater or less than 1.7 V +? 4.8V, immediately activates the Q1 or Q2 of each. With the activation of the transistors of the input level decreases [+] by IC1B, so turn off and RL1. Another section of the protection for us, the heat protection.

This is using the temperature sensor of RTH, the resistance of the PTC (positive temperature factor) has is found and placed back over the heat sink, where the transistors are found. The price to increase with temperature, the potential of the input [-] by IC1A, goes up to the level of input [+], which is determined by the voltage divider R2-3 determined. Once the level of the input [-] are higher than the level of input [+] IC1A exit again at a low level, and the compelling IC2B to change the situation, turn the RL1 and put the D5, which show the thermal protection. The circuit is above the current designation of the thermal protection 70? C. If it? S instability presented in this phase, the effect of RL1 should be changed from the R4, with other smaller prizes. The circuit was in the magazine? Output? 12/95.

Continuity Tester Circuit

     Welcome back to Free circuit dot com ,Today we would like to present you with sound tester circuit .

Regarding description will show thus as below .

    The speaker output is not strong, but it is more than adequate for the purpose. I used a loudspeaker small transistor radio with an impedance of 25-80 ohms. Resistance should be reduced to 300 ohms by adding series resistance R8. For example, if your speaker is 58 ohms, then R8 = 242 ohms. Experience is the value of a C1 or C2 to select an oscillation frequency products coinsides mechanical resonance frequency of the speaker in the particular use.

After choosing the right value, which is probably in the range of 10n – 100N, the tone becomes louder and more earpiercing. A D2 “freewheeling” diode is connected through the sensor as the fast switching of sction oscillator circuit can produce a surprisingly large effect of self through the coil and these high voltages could lead to a breach of other transistor damage. Zener diodes do not provide an absolute voltage drop constandt regardless of the current, 0.8 mA on the design of a 8.2 volt diode existing will probably provide only about 8.0 volt drop from the current test selection and marking zener typically 5 mA or more.

  Another possible source of error is the battery, which suggests a nominal 9V gives a new brand can be as much as 9.5 to 9.8 V until slightly rundown and this “surplus” voltage, combined with a “live” znere voltage drop leaves much more than the expected voltage available from the probes. A silicon diode D1 is in series with the Zener voltage of the sensor by creating a new 0.6 volts or more.

  During your final testing and before boxing your circuit, the compound most appropriate A or B is selected for the positive electrode wire. The goal is to complete the oscillator circuit short-circuited probes but to stop an oscillation with the least resistance or the inclusion of a diode (try both directions) between the probes.

   Sensitivity was not because I do not think it’s worth is not necessary and would spoil the simplicity of the circuit. There is no easy way to demonstrate unity against the frame of the offer. Be careful when checking the wiring and the AC line first. Similarly, if checking electronic devices to cover events between Veroboard tracks, as if a crack suspected in a PCB (Printed Circuit Board) to monitor the power first also. Good luck!

Electronic Parts List

R1 = 1K
R2 = 2K2
R3,R4 = 22K
R5 = 2K7
R6,R7 = 56K 9volt Alkaline battery
R8 = *See text suitable loudspeaker
Z1 = 8V2, 1/4 watt
T1 = 2N3905 (PNP)
T2,3,4,5 = 2N3904 (NPN)
D1,D2 = 1N4148
C1,C2 = 22nF housing & probes

Increase current for IC regulator circuit

Although the 78xx series of voltage regulators with different power outputs, you can compare the power generation by stimulating this circuitry. A power transistor is used to provide additional power to the load of the regulator, maintaining a constant voltage.

 Currents up to 650mA is flowing through the regulator, begins above this value and the power transistor to run, which provides additional power to the load. This must be a sufficient heat sink, because it is probably pretty hot.

Suppose you use a 12V regulator, 7812th Input must be a few volts higher to allow for voltage drops. Take 20 volts. Let us also assume that the load to draw 5A.

The power dissipation in the transistor Vce * Ic or (20-12) * 8 = 40 Watt.

There you stay warm in the winter, but you will have a large heatsink with good thermal dissipation needs do. Do you want the output current with a negative regulator, such as increasing the 79xx series, then the circuit is similar, but a kind of power NPN transistor is used instead

Lamp Flasher circuit with MOSFET

Welcome back to free circuit dot com,today we have circuit about control Lamp or call “Lamp Flasher” with MOSFET drive.

The working principle of this circuit is the MOSFET IRF511 and 2, the drive lamp turns on and off.
C1 and C2 with a speed controller works by receiving the voltage at the gate of the MOSFET when the voltage on C turn ON the other would be to drive MOSFET operation.

Power supply for amplifier 100W circuit

Wecome back to free circuit dot com,today we have power supply for your audio amplifier with 100 W V-MOSFET.
The proposed power amplifier for 100W V-MOSFET is what appears in the above figure. It has separated supply for the various stages of supply, output stage, stage driver, power amplifier and phase protection. Anyone who wants can remove parts or add a power supply for each channel, separating completely the channels between them. Attention should be given to ground loops. For anyone who does not use the preamp circuit and protection can suppress the corresponding winding.

Out Voltages For Power Supply
+V1=+60V -V1=-60V
+V2=+12V -V2=-12V
+V3=+65V -V3=-65V

Electronic Parts List
C1….4=15000uF 100V
C5-8=2200uF 25V
C15=33nF 630V

IC1=7812
IC2=7912
C6-9=100nF 100V
C7-10=47uF 25V
C11….14=2200uF 100V
BR1=Bridge 250V 25A
BR2=Bridge 250V 3A
BR3=Bridge 250V 3A
T1=220V / 2X43V AC – 250VA
/2X15V AC – 20VA
/2X46V AC – 40VA
S1= 2X2 switch 250V/10A
F1=Fuse 2A slow

Ultrasonic transmitter and recevier

Welcome back to free circuit dot com,today we have the circuit example describes the ultrasonic remote control switch, remote control distance of 10m or more, can be used in a wide range of industrial automation control and home appliances to control. The ultrasonic remote control circuit consists of an ultrasonic transmitter and receiver circuit switching. Ultrasonic transmitter circuit of the S-key, time-base integrated circuit IC 1, transistors V1, V2, R1 ~ R5, potentiometer RP1, diode VD1, VD2, capacitors C1, C2, and the first ultrasonic transmitter consists of B1, as in statements.

   Ultrasonic transmitter circuit ultrasonic receiver circuit comprises an ultrasonic receiver B2, V3 ~ transistors Q5, operational amplifier integrated circuit IC2, relay K, the diode VD3 ~ ~ VD5 and resistors R6 R15, capacitors C3 to C5, potentiometers RP2 and other components, such as shown.

   
Ultrasonic receiver circuit components chosen selection of R1 ~ R15 1/4W carbon film resistors and metal film resistors. RP1 and RP2 use small glass or sealed variable resistors. Use a high frequency ceramic capacitor C1, C2 ~ C5 with monolithic capacitors and polyester capacitors. VD1 ~ VD5 are made Silicon Switching Diode 1N4148. V1, V3 and V4 are all made from silicon NPN transistor S9014, S9015 V2 and V5 with silicon NPN transistor; V6 uses S9013 or C8050 Silicon NPN transistor. Used to give IC1 NE555 5G1555 or if the base integrated circuit IC 2 μA741 use or CA3140, LF351 to amp models such as integrated circuits. Ultrasonic transmitter selection of the head 82 T40 R40 B1 uses ultrasonic receiver. K 9 V DC relay selection, allows the capacity of visual contact can be controlled by electrical current.

12 to 24 DC to DC Circuit

Welcome back to Free Circuit dot com,today we have DC to DC converter for your apply to power project or amplifier circuit.

So,We prepare both circuits and component layout too.

DC-DC converter provides a maximum power of about 36 watts at an efficiency of 90%. Besides a modern FET and Schottky diode, this circuit is very well known and cheap parts.

Nevertheless, the specifications are excellent

yield: about 90%
ripple: 10 mV.
max Output current: 1.5 A.
maximum switching frequency: 40 kHz
Input voltage: 12 V.

output voltage: 24 V.

12 to 24 DC-DC-Circuit

12 to 24 DC-DC Circuit 3

regulated The switching element is a quick power FET (T8).
This FET has a relatively high input capacitance and switching on and off by a push / pull phase of two RF transistors (T5/T6). Schottky diode D2 increases even more off-speed, which is crucial here because we strive to achieve the highest possible efficiency.

12V to 24 dc to dc component layout

Converter 1000 VA 75-105 Volts Circuit

Welcome back to Free circuit dot com,We will be continue to present the converter circuit for amplifier use  Car power supply.

Regarding you say practical, Converter 1000Watts  at 75V-105V. is too much to ask. You should at least try to 24V. Take a look at this (1250VA, 24V):
It is used to ensure the MOSFET is turned off completely safe from being used to load the internal diodes, so no short circuit.

The converter I wrote, I have tried this transistor and immediately blew the MOSFET. When I wrote this transistor, is all right. The MOSFET output stage,For the diodes and transistors,

Converter 1000VA at 75V-105V PCB

this arrangement in the majority of converters used in Bangladesh and India, as I have seen.

How to Calculate transformer

Vin = Vout (sec / pri) at a frequency of 50kHz.

Voltage to 70 V at voltage Battary 13.8V.
70 = 13.8 (sec / pri).

Thousands of Primary 6, I was around 6 ct 6.

Representation 70 = 13.8 (sec / 6).

Find the coil secondary = primary (Vout / Vin).

= 6 x (70/13.8).

= 31 Turn.
Therefore, 31 cycles were 70V.

If you want to reduce or increase Voltage ,you sould be reduce or increase the frequency of this circuit can be reduced switcing pressure.
If the frequency is too low to heat the Mosfet and fig Coli if high frequency noise than it is to offline Power Amp.

Converter 12v to70V 14000w circuit

Free Circuit dot com Today!,After I had posted many amplifier circuit but not post power supply or switching . So,I have one the DC / DC converter 1400W circuit A combination of modern DC / DC switching power supplies, conversion technology.
A constant voltage and current control circuit implementation of the correction of output voltage variations due to transient variations in input voltage or load in less than 1.5 ms caused. This allows a constant stream of continuous short circuit.

DC / DC converter circuit this simple DC-DC converter up to 70V on a 24V source. It can be used for amplifier,radios, sign lights, relays, horns and other accessories in 24V 12V vehicle with a maximum of about 800 mA. to run.

Converter 12v to70V 14000w PCB

It can be used for a 12V battery of another tax or increasing the voltage just enough to make the necessary efforts to provide a 12V linear regulator. With an operational amplifier as the oscillator to a square coil and other operational amplifier in a ring feedback loop, it will not proceed under varying loads to a stable 24V source for many applications. With a wide output adjustment of this circuit is very versatile.

So,I have assembly picture also thus as below .

Converter 12v to70V 14000w Assembly

Note

Vin = Vout (sec / pri) at a frequency of 50kHz.

Voltage to 70 V voltage Battary 13.8V.
70 = 13.8 (sec / pri).

Thousands of Primary 6, I was around 6 ct 6.

Representation 70 = 13.8 (sec / 6).

Find the coil secondary = primary (Vout / Vin).

= 6 x (70/13.8).

= 31 Turn.
Therefore, 31 cycles were 70V.

If you want to reduce or increase Voltage ,you sould be reduce or increase the frequency of this circuit can be reduced switching pressure.
If the frequency is too low to heat the Mosfet and Coli if high frequency noise than it is to offline Power Amp.

Capacitor Discharge Ignition circuit

The CDI ignition circuit produces a spark from an ignition coil by discharging a capacitor across the first of the coil.
A 2uF capacitor is charged to regarding 340 volts and also the discharge is controlled by an SCR. A Schmitt trigger oscillator (74C14) and MOSFET (IRF510) are used to drive the low voltage aspect of alittle (120/12 volt) power transformer and a voltage doubler arrangement is employed on the high voltage aspect to extend the capacitor voltage to regarding 340 volts.
an analogous Schmitt trigger oscillator is employed to trigger the SCR regarding four times per second. the ability provide is gated off throughout the discharge time so the SCR can stop conducting and come back to it’s blocking state. The diode connected from the 3904 to pin nine of the 74C14 causes the ability provide oscillator to prevent throughout discharge time.
The circuit attracts solely regarding two hundred milliamps from a twelve volt supply and delivers virtually twice the conventional energy of a standard ignition circuit. High voltage from the coil is regarding 10KV employing a 3/8 in. spark gap at traditional air temperature and pressure.
Spark rate may be increased to probably ten Hertz while not losing abundant spark intensity, however is restricted by the low frequency power transformer and duty cycle of the oscillator. For faster spark rates, the next frequency and lower impedance provide would be needed.
Note that the ignition coil isn’t grounded and presents a shock hazard on all of it’s terminals. Use CAUTION when operating the circuit. An alternate methodology of connecting the coil is to ground the (-) terminal and relocate the capacitor between the cathode of the rectifier diode and also the positive coil terminal. The SCR is then placed between ground and also the +340 volt aspect of the capacitor. This reduces the shock hazard and is that the usual configuration in automotive applications.

555 Negative Voltage Generator Circuit

This circuit is power supplies for your hobby project. I have frequent requests for help which indicates that there is often a need to generate a negative voltage RS-232 or other circuits, such as when there are only 5 or 12 volt source that is readily available. I encountered the same problem. There are answers available in trade with these problems, but they are generally bulky, expensive and not readily available when needed, and are not really adaptable to any situation.
For me, the solution came as a draft in the IC 555 back late 70 Sec.  and early 80 Sec. a negative voltage generator quickie. There is nothing new or particularly clever about the design based on one of the most popular channels and versatile product ever. The parties are plentiful and cheap, two of my criteria for DIY projects, in general, they are all part of a junk e-box studio. The circuit is very simple and easily adaptable to different requirements. The circuit can be used to generate twice the supply voltage reverses the polarity of the diode and output capacitor.

SWR and PWR Meter circuit

Many SWR / Power meter used by amateurs to the extent reasonably accurate continuous average power with a CW key-down signal, but can not reliably be used with other (modulated) signals PEP or average power measurement. These laws seek to show why the power measurement can be a sensitive issue, and because the interpretation of a yardstick of power can be a lot of attention and knowledge of construction and the characteristics of the instrument.

 A reflectometer-type SWR meter can be calibrated to give power back and forth (PF, Pr) on a power supply. A classic example is the 1943 Bird Series power meter, which is a directional coupler is used to obtain a sample voltage proportional to the voltage wave or forward or backward on the feeder (VF, VR). Other systems, perhaps more suitable for HF, then use a bridge circuit to perform the same function. The sample voltage is then rectified and displayed on a meter that is calibrated in watts. If the counter is typically a coil, the scale, so the numbers on the scale, representing the power, are proportional to the square of the applied voltage or the current calibration. The theory of this type is very simple and is based on the concept represented by PF = Vf2/Zo. Note that if the power supply has an impedance that differs from the value of how the instrument is calibrated, there will be a mistake. The output voltage of the rectifier is a solid phase of VF or VR, and this is expected in the calibration of the meter.
 Examples of directional coupling, and bridge-type reflectometers are shown in Figures 1 and 2, while the bird directional coupler means 43 is illustrated in Figure 3. Note that in all cases the measurement circuit, a combination with a small RC time constant, making the system unsuitable for the measurement of PEP, and the absence of a specific device quadratic, making them unsuitable for measuring the average power (see discussion of these points below).

High volt genarator circuit

The simple circuit described here is capable of generating up to 2.1 kilovolts or more from a current source with low voltage flyback (LOPT) transformer to recover from a B / W or color TV or computer monitor. Typical output with a 12 VDC 2 A power supply or batteries will be 12,000 V. Maximum output current at full voltage is typically on the order of 1 to 2 mA. Higher currents are available, but decreases the output voltage. A 2 kV, more than 10 mA may be possible depending on your particular flyback transformer input voltage and current.
As you can see the diagram below, does not get much easier than this!

CAUTION: Read the document: “Safety Guidelines for High Voltage and / or equipment for power line” and shoot the circuit!
Read in its entirety!

flyback obtain solutions with high voltage secondary winding. primary may be left intact if it is known to be in good condition – not short-circuited. A flyback removed due to failure can be used if the primary were to fail and the primary turns can be removed without damaging the HV secondary or losing the secondary connection back! Flyback fail in both directions (primary and secondary).

CAUTION:  Locate the return of the winding tension. It can be a different color yarn winding low voltage or the output of the flyback portion of the plate in a different place. You can not use an ohmmeter to locate the return of power Fast-forward if the return to a high-voltage multiplier or HV rectifier diodes rectifiers decline is far greater than the battery voltage used in your meter. However, a connection with a liquidation infinite resistance to all other terminals may be the HV return. The flyback HV rectifier or multiplier without a return can be easily identified by measuring the resistance between the HV output and all other terminals. The high voltage winding has a resistance of 100s-1000 ohms than a single dose of digits or less for all other windings.

Wind 10 turn center tapped winding drive and 4 turn centertapped feedback winding using # 16-20 gauge wire. Make sure that both halves of each coil are wound in the same direction. Log centertap in each case on the settlement – not a show cycle. A good insulation with duct tape.

Vcc should typically be in the range 12-24 volts in a couple of amps. oscillating circuit is scheduled for about a Vcc of 5 V or more. If you do not get the high voltage, reverse the connections to the transistor bases. heat sink is recommended for the transistor. Be aware of the capabilities of your return (B / W monitor up to 15 KV, color up to 30 KV). You risk destroying the secondary windings and / or HV rectifier if you get carried away. Running this on 24 volts will probably cause an internal arc-over in a small flyback, then start again with more caution and a new flyback.

Actual production depends on the turnover of the flyback you have.

For a typical small B / W TV, monochrome screen or a video terminal, you should be able to get around 12,000 volts with 12 VDC.
I built one from a dead Mac-Plus flyback from which I removed the coils (dead) primary.

With a large color television or color monitor flyback, 30,000 V or more will be made possible with 24 VDC.

The operating frequency is in KHz to 10 KHz range depending seconds of VDC, the load and the specific flyback.

You can experiment with the speed, resistance values, etc. to optimize operation and power for your needs.

WARNING: Contact with the output will be painful, but probably not particularly dangerous due to small (few mA) current availability.
HOWEVER, if you add a high voltage capacitor for charge storage, do not even think of approaching the HV!

AC current detection circuit

This circuit will detect power line currents of 250 mA or more without making electrical connections to the line. Current is detected by passing a line of alternating current through an inductive pickup (L1) as a screen diameter of 1 inch U-bolt wound with 800 turns # 30 – # 35 magnet wire.

The pickup could be made from rings of iron or other type of processor core that allows enough space to pass one of the AC lines through the center. Only one of the power line is the line or neutral must come from the center of the pickup to avoid the fields cancel.

I tested the circuit with a 2 wire extension cord that had separated the twin wires a small distance with an exacto knife to allow the U-bolt to encircle a single cable. The magnetic pick-up (U-bolt) produces about 4 millivolts peak for a series of alternating current of 250 mA, or AC load of around 30 watt.

The signal from the pickup has grown about 200 times the output of pin op-amp 7, followed by the peak detected by diode and capacitor connected to pin 7. The second op-amp used as a reference point, which detects voltage increases above the drop pass.

The minimum mark required to cause the comparator output stage is a positive change of 800 mV peak around a power line 30-watt. The 1458 swing op-amp output in just a couple of times the ground so a voltage divider (1K/470) is used to reduce the voltage signal at about 0,7 volt.

An additional diode added in series with transistor base to ensure that off when the voltage op-amp is 2 volts. You can get a piece “of relay chatter if the AC load is close to the switching point so a larger load 50 W or higher recommended. The sensitivity can be increased by adding more becomes a pick-up.

Power supply 0 to 30 V at 2 A circuit

 SPECIFICATION  
 Output voltage (Vout) 0 ….. 30V DC
 Output current (Iout) 0 ….. 2A DC
 Consolidation Load 0.008% (Dion = 1.5a)
 Stabilization Network 0.01% (DIi = 20V)
 Stability of Vo (Vo = 15V, Io = 1A) 0.2% (DI = 15? C, Dt = 90min)
 Ripple and noise of 1mV pp (20HZ. .. 10MHZ)
 Output impedance (Vo = 10V, Io = 1A) 20mO at 1KHZ, 250m at 200KHZ
 operating temperature (ambient) 0-40 ° C

     The basic requirements of a laboratory power supply, is to provide the voltages and currents of operation required by conventional devices have low output impedance, low noise, low ripple and good stabilization. The above requirements are met, the circuit’s power supply.

    Many power supplies have an electronic security protects them from destruction when the output is shorted. The circuit can be configured to use the higher power output at any one value from 0 to 2A and not to exceed, even if the load is greater demand. This not only protects, but also can prevent and device supplies, though the latter tends to draw more power than projected.

     The power supply circuit can be used even for testing components, the profiling voltage / current and used as an ideal source of constant voltage, current, sufficient to provide 0-30V and 0-2A, continuously adjustable, rather than in steps. For the power circuit, the transformer T1 has two secondary windings. A winding supplying the output circuit with high current through D1-4, C2, and the second coil, which feeds the IC1, as rectified by D1, C4 and stabilized by the D7, C5. The current passes through LED D6, which serves as an indicator.

      The C7 offset frequency do within circuit IC1 and R2/D8/D9, to protect against voltage spikes of the network. Me pontesometer R3, regulate the output voltage at the point where we want. By pontesometer R8, adjust the threshold current, we want to exit. At the exit of the feeder is a multi Darlington, consisting of Q1, Q2 and Q3, Q4, connected in parallel. The resistors R14, R15 ensure uniformity of the collector currents, the R10 to R12 improve the stability DC output, which is essential especially at high temperatures, the reverse currents begin to become appreciable. The netting R9, C10, C11 achieves frequency offset in the amplifier output of IC1 and the D13, its protection. Through the R19 passes the output current. The voltage drop occurring at the ends of degraded at a rate and applies to entry 11 of IC1.

       In the second entry 10 of IC1 is applied a constant voltage, the price of which is regulated by the R8, the desired maximum current output. Once the output exceeds this value, the voltage drop at R19, 10 is applied to the input of IC1, thereby activating the differential amplifier in IC1 and prohibit the further increase in power output. The capacitors C13, C14, C15 disconnection make the exit, while the D15 to protect against reverse voltages.

     With this instrument, VA1, we can measure both the voltage and current output, where the position is located switch S2. The position is shown in the circuit, the switch measures the current by sampling the voltage drop onto the R19, by means of R17, R18. To measure the output voltage should move the switch to another location by sampling the output voltage. Fine adjustment is made by R21, R22.

     The transistor Q2, should be placed in a small refrigerator, and Q3, Q4, a heatsink with thermal resistance of 2.6 ° C / W, and well insulated. The arrangement of the feeder can be easily done by using a multimeter, which will connect the output of the feeder. Moving and adjusting the trimmer in conjunction with the main potesometer regulating voltage and current, you can limit the scale will affect the R3, R8. H.N 6-7/77

Electronic Part List

R1= 1.2Kohm 1W
R2-12= 100ohm 
R3= 47Kohm Lin.
R4-7-21= 10Kohm trimmer
R5= 8.2Kohm 
R6-10= 12Kohm 
R8= 470ohm Lin.
R9= 1.2Kohm 
R11= 820ohm 
R13= 560ohm 
R14-15= 0.68ohm 2W
R16= 330ohm 
R17= 470ohm 
R18= 470ohm trimmer
R19= 0.22ohm 2W
R22= 56Kohm 
R20= 3.9Kohm   
C1-3= 330nF 250V D8= IN5236B
C2= 4700uF 63V D9….14= 1N4002
C4= 68uF 63V  
C5= 47uF 40V  
C7-12= 100nF 100V Lin. 
C8= 680nF 100V  
C9-14= 1uF 40V  
C11= 10pF ceramic  
C13= 220uF 40V 2W 
F2= 2A slow Fuse 
S1= 2XON/OFF 10A/250V switch 
D1-4= 15A Bridge trimmer polyester
D5= 1N4002 VA1= 500?A polyester
C10= 220pF ceramic  
S2= 2X2 ON 1A 
F1= 1A/250V slow Fuse
T1=220VAC/ A:34V/4A B:36V/50mA 
C6-15= 10nF 100V polyester
D15= MR501  
Q1= MPSL01  
Q2= 2N4923  
Q3-4= 2N3055  
IC1= MC1466L Motorola 
D6= LED 5mm RED
D7= 1N5252B

Power source checking and alarm

I have most of electrical project for add the power failure indicator circuits want a separate power supply for themselves. But this power supply alarm circuit presented here want no additional supply source.

 It employs an electrolytic capacitor to store adequate charge to power the alarm circuit, an alarm will sound for a reasonable period if the power fails. This circuit can be used as a signal for the power supply ranging from 5V to 15V.

To calibrate the circuit before connecting to the power supply (5 to 15V) and then vary the potentiometer VR1 until the buzzer goes from on to off. Whenever the lack of power, resistance R2 of the base of the transistor and low saturated moves, turning the buzzer.

Active antenna HF-VHF-UHF circuit diagram

This circuit enables the connection of devices with video output in low frequency to the aerial socket of any TV.

The modulator is an oscillator in the VHF / UHF modulated signal from the video taken from the source. The oscillator uses a transistor for high frequency (T1) that generates the carrier wave.

The harmonic generator is made up of diodes D1 and D2 connected in antiparallel to, very fast switching in synchronism with the signal at 27MHz, generating strong harmonics that extend to the GHz band of P1 determines the modulation depth, while P2 regulates polarization oscillator.

The power circuit is not stabilized and may vary between 8V to 30V or 5V settled directly (in this case is not necessary to use the 7805). L1 and L2 are obtained by wrapping 3 turns and a half of enamelled copper wire diameter of 0.2 mm on a ferrite bead 3.5 mm.

L4 is formed of a single coil of copper wire 0.8 mm wrapped in air with a diameter of 8mm. L3 is readily available commercially. For calibration the following steps: set the TV up to full brightness and contrast, apply a video signal input circuit and connect the output of the TV antenna.

Rotate P1 and P2 in a central location so that it is completely at the slightest resistance. Tune the TV to a frequency to eliminate the “snow” or until the screen becomes completely black. Rotate P1 until the picture is not visible on TV and then act on P2 to obtain the best possible result.

3-24volt regulator

voltage comparator circuit

In the circuit having a voltage quad comparator (LM339) is used as a simple bar graph meter to indicate the state of charge 12-volt lead-acid battery acid. A 5 volt reference voltage is in each of the (+) inputs of four comparators and the (-) inputs are connected, each point is connected to a voltage divider. The LED lights up when the voltage at the negative (-)-input exceeds the reference voltage. Calibration can be by adjusting the 2K potentiometer so that all four LEDs illuminate when the battery voltage is 12.7 volts indicates a full charge with no load on the battery is done. At 11.7 volts, the LED should be made, and shows an empty battery. Each LED is a change of about 25% charge or 300 millivolts, so that 3 LEDs indicate 75%, 2 LEDs indicate 50%, etc.

The actual voltage on the temperature and battery type from, battery wet gel battery, etc . For more information on battery care.

IR remote controller Circuit

I have a number of switch / out with an infrared remote control TV as a transmitter, which is great for me to work yet there is something that I add, or you must remove or change to better? 4013 is configured to switch on / off switch, namely the production will remain high until the clock is replaced by a high level, and will remain until replaced by another , then the output will go low, and so on. if the TV remote control is pressed, it sends the signal (pulse) to the receiver, making the CLK output transistors have to activate the double flip-flop IC, I, nor the 47uF capacitor, so if it is considered that the pulse is High input CLK, while the TV remote control is pressed when you press the remote (off), the pull-down resistor 10K, stream discharge capacitor and the output remains high until the process happens again, then the output remains low, and so on.

Flyback 10KV-30KV Circuit

The primary is a handwound coil wound on the opposite side of the secondary consisting of ten turns of 16 guage solid wire. The feedback winding is wound on top of the primary winding with four turns of 22 guage solid wire. Both windings are center tapped. If there is no high voltage from the secondary winding then try reversing the leads that go to the bases on the transistor. These must be in phase for proper operation. The 2N3055s can be replaced with about any large horizontal output transistor, in fact this is actually better. You can also use a PNP transistor, just reverse the polarity of the input.

As you can see what metal a good selection of beat-frequency operation (BFO), up to 90 mm for a bottle-top. In fact, for the ultimate in simplicity, the capacitor C1 is omitted. In this way, the author reaches is astonishing, 150mm range for the bottle top. But with the frequency then to more than 4 MHz, the instability is a major problem.

Metal Detector Schematic

metal detector circuit

As shown in the circuit, oscillates at 230kHz. You can also experiment with the frequency by changing the value of C1. Faraday shield can be added to reduce ground-effect and capacitive coupling, and this is connected to 0V.
Since the inductance is resistance to rapid change in voltage, the charging of fees C1 delayed a bit like the logical level IC1a 2-pole change. This requires a rapid oscillations, which is repealed by an AM radio. Any change in the inductance in the search coil (by the presence of metal) to a change in the oscillator frequency. Although 230kHz is out of reach for the medium-wave band, an AM radio will significantly increase this frequency harmonics.

Metal detector calibration
This makes the search coil L1 is much room for error and is not far from conclusive. The author uses seventy turns 30 s.w.g. (0,315 mm) copper wire on a former 120mm diameter.
The metal detector, set up by the AM radio to pick up a whistle. Not all of these harmonic functions well, and are best suited to. The presence of metal will significantly change the sound of the whistle.

* Metal Detector FAQ *
This is not an industry or security metal detector and is not even near loma or ERIEZ metal detection system. It’s just a notebook, but not hand-metal detector.

18-36 power control

This power supply circuit is adjustable 18-36 volts and is currently shown as being limited to 2 amps, but up to 3 amps in a small current sense resistor of Options (0.3 ohm). 2N3055 and 2N3053 transistors should be in wells. very hot right now and resistance is to be made at 3 watts or more. Voltage, which is controlled by 1 / 2 of the LM1458 Op Amp, or 1458-AMP. It can be replaced in the circuit below, but sources indicate pressure. Pin 8 to 30 VDC supply is limited, which may increase by 6.2 Vdc or 5.1 Vdc. Zener K-series resistance, is 8-pin. Maximum supply voltage DC for LM1458 and LM1558 are 36 and 44, respectively.

    Should be the power transformer. As expected the power supply. Enter at least 4 times the desired output voltage, but can not exceed the op-amp under conditions of low stress. Transformer is used as a center, see 25.2 volts AC / AMP 2 units to regulate the 24 volts at 0.7 amps, 15 volts at 2 amps or 6 volts at 3 amps. Output AMP 3 is the center of the water. Transformer that changes the position of 18 volts. All components must be an exception from Radio Shack LM1458 op-amp.

10A power supply

If you don’t know ,”How to build regulator circuit ” for your project or equipment, I think this simply circuit will be to apply in your project .

I leads the old equipment to come and give a very generous and say I pray for DC power supply circuit 10A.

What a simple please, when I saw the equipment they already have. Then take this route, please use the 78xx chips such as IC 7805 =output 5 Vdc.

IC 7809 =output 9 Vdc.

IC 7810 =output 10Vdc.

IC 7812=output 12 Vdc.

Many have the number and strength M15004 number of transistors that can increase the flow. Obtaining high range 10A.The important aspect Transfermer that you need about the current 10A. And using C-format 10000UF with Filter.

water level sensor circuit

For circuit not only indicates the amount of water in the tank head, but also gives an alarm when the tank is full.
This circuit uses the widely available to show IC number CD4066 bilateral switch CMOS IC to the water level through LEDs.
If the water is empty the wires in the tank are open circuit and the 180K resistors pulls the switch to open the little switches and LEDs are off. When the water begins to fill the first wire connected to the reservoir in the S1 and the + supply are shorted by water. This closes the S1 and turns the LED1 ON. As the water further into the tank, LEDS2, 3 to 4 pm light gradually filled.
No. Levels of the display to 8 if 2 can CD4066 ICs are used to increase similarly.

If the water is full, the base of the transistor BC148 is pulled up with water and saturate the transistor, turning the buzzer ON. The SPST switch has to be opened to turn off the ringer.
Remember, the switch ON while pumping water otherwise the buzzer does not sound!

electric power controller circuit

The equipment which can be controlled The equipment which works by the resistance. Such as the the tungsten-filament lamp, the soldering iron and so on. The equipment which is using the AC series motor(with the brush). Such as the drill, the electric fan, the cleaner and so on. The equipment which can not do the control The fluorescence light. The synchronous motor(using the capacitor) As for the synchronous motor, the number of rotations is decided by the frequency of the alternating current. So, basically, it isn’t possible to control with the circuit this time. However, the torque(power to turn) of the motor declines when the electric current which flows through the synchronous motor decreases. With it, the revolution can be slowed down. In this case, with the load which is applied to the axis of the motor, the number of rotations isn’t constant. The electric power which can be controlled is decided by the permission value of the electric current which can pour into the TRIAC. I used the TRIAC which can apply the 12-A electric current to the circuit this time. In the calculation, in case of AC 100V, a maximum of 1200 W can be controlled but in the actual use, about 700 W or 800 W are safe.

6V to 12V Converter Circuit

Electronic Part List

R1, R4 2 .2 K 1/4W Resistor
R2, R3 47K 1/4W Resistor
R5 1K 1/4W Resistor
R6 15K 1/4W Resistor
R7 33K 1/4W Resistor
R8 10K 1/4W Resistor
C1, C2 0.1uF Ceramic Disc Capacitor
C3 470uF 25V electrolytic capacitor
1N914 diode D1
D2 Diode 1N4004
D3 12V 400mW Zener Diode
Q1, Q2, Q4 BC547 NPN transistor
BD679 NPN transistor Q3
L1 See Notes
Notes
1. L1 is a custom inductor wound with about 80 turns 0.5 mm magnet wire a ring around the core with an outer diameter of 40 mm.

2. Different values of D3 can be used to obtain different output voltages from 0.6V to 30V is about. Note that at higher voltages, the circuit could perform just as well and can not produce much electricity. You may need to use a larger C3 for higher voltages and / or higher currents.

3. You can use a larger value for C3, in order to achieve a better filtering.

4. The circuit requires about 2A from the 6V supply to provide the full 800mA at 12V.

The time sequence is generated using the CMOS 4017 decade counter and timer 555th Counter outputs 1 to 4 ares wire ORed with 4 LEDs, so the Red (- north / south) and (Green – East / West) LEDs will for the first four counts.

The fifth count (pin 10) illuminates (Yellow – East / West) and (Red – North / South).

Counts from 6 to 9 ares also wire or diodes control (Red – East / West) and (Green – North / South). Count 10 (pin 11) controls (Red – East / West) and (Yellow – North / South).

Deadline for red and green lights will be 4 times longer than the yellow and time to complete the cycle can be adjusted with the 47K resistor. 1N914 diodes eight could be subsituted with a dual 4 input or gate (CD4072).

LED traffic control circuit

Electrinic Part List

LM555              IC                  1pc.
CD4017             IC                 1pc.
2N3904             Transistor         4 pc
10K Ohms         Resistor          1pc.
47K Ohms          Resistor          1pc.
180 Ohms          Resistor          2pc.
Red                      LED               1pc.
Yellow              LED               1pc.
Green               LED               1pc.
1N914               Diode             8pc.
10uF/16V          Capacitor        1pc.
9V battery clips  Connector      1pc. (option)
PCB                                      1pc.

RLX resistor determines the brightness of the LED and current limiting for about 10 to 15mA when running between 9V to 12 VDC.
TRAFFIC flash scrolling speed is determined by the capacitors C1 and resistance R1 – C1 increases and reductions in R1, the slow speed.
For example, if the LM555 is set to generate one pulse per second, 1 Hz, the green light for 4 seconds to 1 yellow, red for 5

With the main power IC TDA1554 Powered, operates this route to 22W. A few external components that support for the main component. Heat sink on the power IC is a must.

Components:

R1__________39K 1 / 4 watt resistor
C1, C2_______10uf 25V electrolytic capacitor
C3__________100uf 25V electrolytic capacitor
C4__________47uf 25V electrolytic capacitor
C5__________0.1uf 25V ceramic capacitor

22w_amp_TDA1554_Circuit

C6__________2200uf 25V electrolytic capacitor
U1__________TDA1554 Two Channel Audio Amp Chip
MISC________Heatsink For U1, Binding Posts (For Output), RCA jacks will (for input) This works best with 4 ohm speakers, 8 ohm operation, but do. This circuit has gone about 28 watts of heat, so that’s a good heatsink is required. The chip should run cool enough to touch the heatsink correctly installed.
Operated at 12 volts and about 5 amps at full volume. Small amounts consume less power and thus produce less heat. PCB is preferred, but universal solder or perf board will do. Keep lead length short.

22W Audio Amplifier PCB

2W switch power supply circuit

It is to compensate the reduction of output power due to low voltage supply the transistor uses the Bridge-Tied-Load principle (BTL) which can provide an output of around 1.5 to 2 W at 14Vdc with a power supply of 6 V.

For the circuit the potentiometer can be used to control the voltage. Capacitor C1 and C2 are meant for filtering the supply voltage if a battery eliminator is used as supply source. For operations using a battery C1 and C2 are no necessary.

The work of the power supply is the gain of 2N3053 2N3906 and 2N3904 is fixed internally at 2Watts.
It is to compensate the reduction of output power due to low voltage supply the transistor uses the Bridge-Tied-Load principle (BTL) which can provide an output of around 1.5 to 2 W at 14Vdc with a power supply of 6 V.

For the circuit the potentiometer can be used to control the voltage. Capacitor C1 and C2 are meant for filtering the supply voltage if a battery eliminator is used as supply source. For operations using a battery C1 and C2 are no necessary.

Figure 1 gives a stripboard layout for the 6V regulated power supply shown in figure 1.
The layout does not include the transformer block, so the input to the board needs to be 6V AC from a suitable transformer. 
The layout includes space for two optional 2-way screw terminal blocks to make connecting up the power supply easier.

If the input voltage is 6V AC, you will be able to draw 1A from the power supply.  For the maximum input voltage of 14V you will be able to draw 2W.

50 Watt apmplifier with TDA1514A

Here is circuit audio amplifiers for car, which use it only number Transistor Circuit of IC, simple Circuit (and Top Popula)
Use TDA1514A transistor at low cost. It best Idea Circuit.

LM317 Variable Power Supply Regulator

A circuit is timeless. LM317 regulator is a versatile and highly efficient 1.2-37V voltage can provide up to 1.5 Amps. of current with a large heat sink.

dual regulator power supply circuit

High current voltage regulator circuit

5 Volts Switching Power supply circuit

A transistor the energy is  at 4 volts through him and for 3 amperes through it, may solve approximately 12 watts of heat the problem is from the group of regulators.

When a MOSFET or saturated with 1 volt-ampere in diameter and 3 are only 3 watts. But then on a Mosfet or can not be controlled or monitored  So, that we transform ON and OFF very quickly, so that the amount of current or voltage is supplied.

 The way to do this is PWM – Pulse Width Modulation. In this sense, the MOSFET or transistor is an ON-OFF ie 100 kHz  but the length is variable to the output. The longest duration of time or energy on the stamp is.

Losses are dependent on the speed of the rise and fall of both impulses. The Chopped pulsed DC or AC can be smoothed average with capacitors and inductors. The reagents of the inductor must pulses by a 1N5817 Schottky Rectifier – 20V LED-1A of fast, with low loss. The circuit is on an assessment of the application of the LM2575 is an integrated power supply from National Semiconductor, the details are here LM2575 An application of semiconductors, it shows how this chip may be used to mitigate negative Positive Voltage Power Supplies tensions.

Switching Power Supply 14 Volts 2W Circuit

DC-DC converter 5 to30 V circuit

This project in adjustable voltage for power source  is DC-DC Converter 5 to 30 Voltage circuit with IC CD1846P

power supply 1.2-25 Vdc circuit

The Circuit Variable Power Supply Regulation ,You can adjust Voltage for output 1.2Voltage to 30Voltage at Current 5Amp . This circuit used IC LM350T – 3-Amp Adjustable Regulator
IC LM350T to Hold Heatsink. INPUT Voltage 35V 4A, OUTPUT 1.2V to 33V 3A.

power supply with 7805,7806,7809,7810,7812 at 5A circuit

Just like the famous LM317, the 78xx family incorporates automatic shutdown in case of overheating. You can get up to 1.5A of current with a suitable heat sink. No fuse is required.

Problems:

Observe all the safety precautions when dealing with mains powered circuits.

Possible uses:

A regulated power supply for any application.

Adjustable Power supply 0-30 Vdc /5A circuit

Accessories List

R1=1.2Kohm C1=4700uF/63V IC1=LM723 V1=0-30V DC
R2=680ohm C2=100nF63V MKT Q1=2N3055 TR1=220VAC/ 27V 4A

R3=0.33ohm/5W C3=4.7nF63V

MKT B1=Brindge 100V 5A S1=2×10A SW
R4=15Kohm C4=220uF/63V F1=0.5A Fast Fuse 
R5=3.9Kohm P1=4K7 LOG. POT. F2=2A Slow Fuse  

Notes

1. This regulator in circuit comes in a TO-3 case and must be used with a large heatsink. You should be to mount a small fan to blow air across the regulator .
2. For the filter capacitor is large. The filter won’t fit on any board that bolt it to the case.
3. You can, of course, add a volt and amp meter.
4. Since this project operates from 120 VAC, you must include a fuse and build the project in a case.

13.8 Vdc High current power supply circuit 2

The circuit is high current power supply  which is 13.8V at 20A. That, we can get base equipment which seeks to buy easy, IC LM741 ,founction one’s position voltage be stable or regulated at 13.8V.

which can fine decorate a little again. Besides still have the power transistors 2N3055 X4 numbers bring to build parallel perform enlarge current tall arrive at 20Amp Other detail , Please understand in the circuit.

13.8 high current power supply circuit 2

Timer Power On Relay Circuit

Most any bi-polar transistor may be used, but the zener voltage will vary from about 6 to 9 volts depending on the particular transistor used. Time delay is roughly 7 seconds using a 47K resistor and 100uF capacitor and can be reduced by reducing the R or C values.

Longer delays can be obtained with a larger capacitor, the timing resistor probably shouldn’t be increased past 47K. The circuit should work with most any 12 volt DC relay that has a coil resistance of 75 ohms or more. The 10K resistor connected across the supply provides a discharge path for the capacitor when power is turned off and is not needed if the power supply already has a bleeder resistor.

-Variable power supplies muti-rate.
-Constant current regulators.
-Battery chargers.

Project Features
-Variable output down to 1.2Vol.
- 3 Amp output current
- Thermal regulation
-Output is short circuit protected
- Amp of Current limit constant with temperature

Power Off Relay Timer Circuit

      The circuit on the left is a common collector or emitter follower and has the advantage of one less part since a resistor is not needed in series with the transistor base. However the voltage across the relay coil will be two diode drops less than the supply voltage, or about 11 volts for a 12.5 volt input. The common emitter configuration on the right offers the advantage of the full supply voltage across the load for most of the delay time, which makes the relay pull-in and drop-out voltages less of a concern but requires an extra resistor in series with transistor base. The common emitter (circuit on the right) is the better circuit since the series base resistor can be selected to obtain the desired delay time whereas the capacitor must be selected for the common collector (or an additional resistor used in parallel with the capacitor). The time delay for the common emitter will be approximately 3 time constants or 3*R*C. The capacitor/resistor values can be worked out from the relay coil current and transistor gain. For example a 120 ohm relay coil will draw 100 mA at 12 volts and assumming a transistor gain of 30, the base current will be 100/30 = 3 mA. The voltage across the resistor will be the supply voltage minus two diode drops or 12-1.4 = 10.6. The resistor value will be the voltage/current = 10.6/0.003 = 3533 or about 3.6K. The capacitor value for a 15 second delay will be 15/3R = 1327 uF. We can use a standard 1000 uF capacitor and increase the resistor proportionally to get 15 seconds.