Sunday, March 31, 2013
Pump it up Mp3 Booster
MP3 players are all the rage these days. The smaller ones in memory-stick format are particularly easy to take with you; your very own ‘personal sound system’ on the move! It’s when you want others to share your taste in music that you find these players to have a lack of power. You can get round this problem with the help of the MP3 booster, a small amplifier that can be used to connect your MP3 player directly to your Hi-Fi. When you next invite your friends to a party you can ask them to bring their ‘personal music’ as well as the usual drinks!
But first we have to build this booster! The small battery-powered players have an output signal that is more than sufficient to drive a set of 32 Ohm headphones. You’ll often find that with an output of 1mW the sound pressure level (SPL) produced can reach up to 90 dB. This would be sufficient to cause permanent damage to your hearing after only one hour! The maximum output voltage will then be around 200mV. This, however, is insufficient to fully drive a power amplifier. For this you’ll need an extra circuit that boosts the output voltage.
Power amps usually require 1 V for maximum output, hence the signal has to be amplified by a factor of five. We will also have to bear in mind that quieter recordings may need to be amplified even more. We’ve used a simple method here to select the gain, which avoids the use of potentiometers. After all, the MP3 player already has its own volume control. We decided to have two gain settings on the booster, one of three times and the other ten times. Amplifiers IC1A and IC1B (for the right and left channels) are housed in a single package, a TS922IN.
The output signal of the MP3 player is fed via a stereo cable and socket K1 to the inputs of the amplifiers. The gain depends on the relationship between resistors R2 and R1 (R6 and R5 for the other channel) and is equal to ten times. When you add jumper JP1 (JP2), resistor R3 (R7) will be connected in parallel with the negative feedback resistor R1 (R6), which causes the gain to be reduced to about three. When you start using the booster you can decide which gain setting works best for you.
But first we have to build this booster! The small battery-powered players have an output signal that is more than sufficient to drive a set of 32 Ohm headphones. You’ll often find that with an output of 1mW the sound pressure level (SPL) produced can reach up to 90 dB. This would be sufficient to cause permanent damage to your hearing after only one hour! The maximum output voltage will then be around 200mV. This, however, is insufficient to fully drive a power amplifier. For this you’ll need an extra circuit that boosts the output voltage.
Power amps usually require 1 V for maximum output, hence the signal has to be amplified by a factor of five. We will also have to bear in mind that quieter recordings may need to be amplified even more. We’ve used a simple method here to select the gain, which avoids the use of potentiometers. After all, the MP3 player already has its own volume control. We decided to have two gain settings on the booster, one of three times and the other ten times. Amplifiers IC1A and IC1B (for the right and left channels) are housed in a single package, a TS922IN.
The output signal of the MP3 player is fed via a stereo cable and socket K1 to the inputs of the amplifiers. The gain depends on the relationship between resistors R2 and R1 (R6 and R5 for the other channel) and is equal to ten times. When you add jumper JP1 (JP2), resistor R3 (R7) will be connected in parallel with the negative feedback resistor R1 (R6), which causes the gain to be reduced to about three. When you start using the booster you can decide which gain setting works best for you.
Circuit diagram:
MP3 Booster Circuit DiagramResistor R4 (R8) takes the amplified MP3 signal to the output socket K2 (K3). A cable then connects these phono sockets to the input of your power amplifier. The resistors connected in series with the output (R4 and R8) are there to keep the booster stable when a long cable is connected to its output. Cables have an unwelcome, parasitic capacitance. This capacitive effect could (due to phase shifts of the signal) affect the negative feedback of the booster in such a way that a positive feed back occurs, with the result that the booster oscillates and possibly damages the power amplifier!
The resistors (R4 and R8) effectively isolate the output of the booster from the parasitic capacitance of the output cable. They also protect the booster outputs from short circuits. We’ve used a TS922IN opamp in this booster because it can operate at very low supply voltages (the maximum is only 12 V!), but can still output a reasonable current (80 mA max.). For the supply we’ve used rechargeable batteries (e.g. NiCd or NiMH cells) so that we don’t need a mains supply.
To keep the number of cells required as small as possible, we’ve chosen a supply voltage of 5 volt; this can be supplied by four rechargeable batteries. It is also possible to use four ordinary, non-rechargeable batteries; it’s true that the supply voltage then becomes a bit higher (6 Volts), but that won’t cause any harm. Since we’ve used a symmetrical supply for the booster (2 x 2 batteries), it will be easiest if you use two separate battery holders, each with two AA cells. The two holders are connected in series.
Make sure that the batteries are connected the right way round; the positive of one always has to be connected to the negative of the next. This also applies to the connection between the two battery holders. S1A/B is a double pole switch, which is used to turn both halves of the battery supply on or off simultaneously. If you can’t find the (dual) opamp we’ve used (or an equivalent), you could always use standard opamps such as the NE5532, TL082 or TL072. These do need a higher supply voltage to operate properly. In these cases you should use two 9 V batteries and replace resistor R9 with a 15 kΩ one.
Do take care when you connect the circuit to your power amplifier because the output signal can be a lot larger and you could overload the power amplifier. (Although you’re more likely to damage the loudspeakers, rather than the amplifier!) (Please note that these two 9 V batteries can’t be used as a supply for the TS922IN!) In our circuit we’ve used a stereo jack socket for the input and phono sockets for the output because these are the most compatible with MP3 players and power amplifiers respectively. If you wanted to, you could solder shielded cables directly to the circuit instead, with the correct plugs on the ends. You’ll never find yourself without the correct connection leads in that case!
The resistors (R4 and R8) effectively isolate the output of the booster from the parasitic capacitance of the output cable. They also protect the booster outputs from short circuits. We’ve used a TS922IN opamp in this booster because it can operate at very low supply voltages (the maximum is only 12 V!), but can still output a reasonable current (80 mA max.). For the supply we’ve used rechargeable batteries (e.g. NiCd or NiMH cells) so that we don’t need a mains supply.
To keep the number of cells required as small as possible, we’ve chosen a supply voltage of 5 volt; this can be supplied by four rechargeable batteries. It is also possible to use four ordinary, non-rechargeable batteries; it’s true that the supply voltage then becomes a bit higher (6 Volts), but that won’t cause any harm. Since we’ve used a symmetrical supply for the booster (2 x 2 batteries), it will be easiest if you use two separate battery holders, each with two AA cells. The two holders are connected in series.
Make sure that the batteries are connected the right way round; the positive of one always has to be connected to the negative of the next. This also applies to the connection between the two battery holders. S1A/B is a double pole switch, which is used to turn both halves of the battery supply on or off simultaneously. If you can’t find the (dual) opamp we’ve used (or an equivalent), you could always use standard opamps such as the NE5532, TL082 or TL072. These do need a higher supply voltage to operate properly. In these cases you should use two 9 V batteries and replace resistor R9 with a 15 kΩ one.
Do take care when you connect the circuit to your power amplifier because the output signal can be a lot larger and you could overload the power amplifier. (Although you’re more likely to damage the loudspeakers, rather than the amplifier!) (Please note that these two 9 V batteries can’t be used as a supply for the TS922IN!) In our circuit we’ve used a stereo jack socket for the input and phono sockets for the output because these are the most compatible with MP3 players and power amplifiers respectively. If you wanted to, you could solder shielded cables directly to the circuit instead, with the correct plugs on the ends. You’ll never find yourself without the correct connection leads in that case!
Source: www.extremecircuits.net
How to Make a Simple 12 Volt LED Lantern Circuit
We have discussed white LEDs comprehensively through many of my earlier articles and have learned how efficient these lights are with power consumption.
In this article we will study a very simple configuration for making a LED lamp or a LED lantern.
New electronic enthusiasts often get confused with the wiring intricacies while configuring many LEDs in groups.
Here we’ll see how we can connect as many as 64 LEDs for making the proposed unit.
The circuit diagram details may be understood from the following points:
White LEDs typically have a forward voltage drop of about 3 volts.
When operated at the above voltage level, the device is able to produce lights at optimum levels and the spec also maintains better life expectancy.
The minimum current required at the above voltage level is around 20 mA, which again is an optimal magnitude and is ideally suited for a white LED.
That means for driving a single white LED in the most straightforward way we would require 3 * 0.02 = 0.06 watts, that’s pretty negligible compared to the relative illumination received from it.
The best thing is that as long as the above voltage and current spec is observed, the device continues to consume 0.06 watts irrespective of the number of LEDs connected.
In the present circuit, the maximum voltage available is 12, dividing 12 by 3 = 4, meaning 4 numbers of LEDs can be accommodated at this voltage and yet we are able to limit the power to 0.06 watts.
However the above calculation would make the circuit quite vulnerable to voltage drops and if the voltage dropped even by a single volt would make the LED too dim or might just shut them OFF, we don’t want this to happen.
Therefore though the efficiency may drop a bit, we opt for a configuration which would enable the circuit to work even at lower voltages. We include only two LEDs in the series @ o.06 watts.
Now it’s all about connecting the desired number of strings of two LEDs each in parallel until all the 64 bulbs are included in the circuit.
However connecting in parallel would mean multiplying current. Since we have 32 parallel connections means the total consumption will now become 32 * 0.06 = 1.92 watts, still pretty much reasonable.
The connection details can be easily traced from the given schematic.
Your simple LED lantern is ready and may be taken anywhere outdoors with you, probably during night time explorations.
Pats List
All resistors are = 470 Ohms, 1.4 watts,
All LEDs are = white, 5mm, hi-efficiency
Diode = 1N4007
USB Operated Home Appliances Cicuit
When turning a computer on and off, various peripherals (such as printers, screen, scanner, etc.) often have to be turned on and off as well. By using the 5-V supply voltage from the USB interface on the PC, all these peripherals can easily be switched on and off at the same time as the PC. This principle can also be used with other appliances that have a USB interface (such as modern TVs and radios). This so-called ‘USB-standby-killer’ can be realized with just 5 components. The USB output voltage provides for the activation of the triac opto-driver (MOC3043) which has zero-crossing detection. This, in turn, drives the TRIAC, type BT126.
Circuit diagram:
USB Operated Home Appliances Circuit Diagram
The circuit shown is used by the author for switching loads with a total power of about 150 W and is protected with a 1-A fuse. The circuit can easily handle much larger loads however. In that case and/or when using a very inductive load a so-called snubber network is required across the triac. The value of the fuse will also need to be changed as appropriate. The circuit can easily be built into a mains multi-way powerboard. Make sure you have good isolation between the USB and mains sections.
Source : www.extremecircuits.net
Mech Tech Notes Solid Mechanics
Aircraft Mechanics Fix Airplane Components Such As This Engine.
57 Bombers And Recon Aircraft Were Builtby Aircraft Mechanic Inc.
How To Start An Aircraft Mechanic School Ehow Com.
Mech 353 Tech Notes Solid Mechanics.
Mit Einem Einziehfahrwerk Von Yellow Aircraft Die Mechanik.
Aircraft Mechanic Schools In New York My A And P License.
Technical English Training For Aircraft Mechanics Holland.
Type D 1 Redskin Jacket Aircraft Mechanic S Type D 1 Als Simple Warme.
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Proud Aircraft Mechanic Pins From Zazzle Com.
Standard Plug Wiring Diagrampageford Truck
Standard Seven Way Plug Wiring Diagram Page 2 Ford Truck.
Heavy Metal Photos Trailer Light Diagram.
Wiring Diagram For Bumper Pull Dump Trailers And Roll Off Dump.
Trailer Pulling Information.
Axle Trailer Axles And Running Gear Components Trailer Plug Wiring.
Generic Diagram Of Trailer Wiring.
Trailer Wiring Connector Diagrams For 6 7 Conductor Plugs.
Wiring Diagram For Trailers Caravans.
Trailer Circuit Wiring.
Pin S Type Caravan Wiring Uk Trailer Parts.
Saturday, March 30, 2013
MOSFET IRF 350 as Power Follower
The circuit consists of an N-Channel MOSFET voltage follower T1 (common Drain) and current source T2 (NPN Darlington). Current source is set to 2.2 Amps. With 40V of supply voltage the circuit is able to deliver about 17W into an 8 Ohm loudspeaker. The amplifier will take 88W from the power supply all the time. Bandwidth (-3dB) is from 4Hz to 250 kHz. Rise time is 1.5 us. Output resistance is 0.16 Ohm. The circuit is very tolerant of different kinds of load. Input resistance is 10 KOhm (R0), but can be increased up to 100 KOhm (R4) by omitting R0. Input capacitance remains relatively high, about 1500 pF. For this reason, the preamp should not have higher output impedance than 1 KOhm to maintain high frequency limit about 100 kHz. An input potentiometer can be used instead of R0.
If the value of the potentiometer is 5 kOhm then the high frequency limit will be about 70 kHz. The power follower can be connected directly to the output of CD player, and for reduction of volume potentiometer 5 kOhm can be used.
Normally, the thermal coefficient of zener voltage of 3V type is negative, and so is Ube voltage of the Darlington transistor. As Ube is reduced by -2mV/°C, zener voltage also goes down with increasing temperature inside a box (but the zener is not on the heat sink of the MOSFET and should not be). In fact there was a fluctuation of 40mA at 2A constant current, from my point of view it is negligible. Of course the heat sink for T1 and T2 should be better than 0.5°C/W for each transistor, so four such heat sinks are needed for stereo.
If the value of the potentiometer is 5 kOhm then the high frequency limit will be about 70 kHz. The power follower can be connected directly to the output of CD player, and for reduction of volume potentiometer 5 kOhm can be used.
Normally, the thermal coefficient of zener voltage of 3V type is negative, and so is Ube voltage of the Darlington transistor. As Ube is reduced by -2mV/°C, zener voltage also goes down with increasing temperature inside a box (but the zener is not on the heat sink of the MOSFET and should not be). In fact there was a fluctuation of 40mA at 2A constant current, from my point of view it is negligible. Of course the heat sink for T1 and T2 should be better than 0.5°C/W for each transistor, so four such heat sinks are needed for stereo.
Voltage Levels Control Relays
This circuit proves that microcoprocessors, PCs and the latest ultra-accurate DACs are overkill when it comes to controlling four relays in sequence in response to arising control voltage in the range 2.4 V –12 V. By using equal resistors in ladder network R1-R5, equal intervals are created between the voltages that switch on the relays in sequence. Each resistors drops 1/5th of the supply voltage or 2.4 V in this case, so we get +2.4 V = Re1, +4.8 V = Re2, +7.2 V = Re3, +9.6 V = Re4. Obviously, these switching levels vary along with the supply voltage, hence the need to employ a stabilised power supply. Looking at the lowest level switching stage, when the control voltage exceeds 2.4 V, IC1 will flip its output to (nearly) the supply level. The resulting current sent into the base of T1 is limited to about 1 mA by R6. With T1 driven hard, relay Re1 is energised by the collector current. Because the BC548 has a maximum collector current spec of 100 mA, the relay coil resistance must not be smaller than 120 ohms.
Circuit diagram:
Nearly all current consumed by the circuit goes on account of the relay coils, so depending on your relays a pretty hefty power supply of up to 500 mA may be required. When dimensioning the ladder network to create the desired switching levels, it is good to remember that the 741 will not operate very well with input voltages below 1.5 V or above 10.5 V, while voltage levels outside the supply range (i.e., negative or above +12 V) are out of the question. If you do need a switching level in the range 0-1.5 V, consider using an LM324, which contains four opamps in one package. For the high side of the range (10.5 to 12 V), a TL084 or a ‘rail-to-rail’ opamp like the TS924 is required. However, the TS924 cannot be used with supply voltages above 12 V.
[Continue reading]
Circuit diagram:
Nearly all current consumed by the circuit goes on account of the relay coils, so depending on your relays a pretty hefty power supply of up to 500 mA may be required. When dimensioning the ladder network to create the desired switching levels, it is good to remember that the 741 will not operate very well with input voltages below 1.5 V or above 10.5 V, while voltage levels outside the supply range (i.e., negative or above +12 V) are out of the question. If you do need a switching level in the range 0-1.5 V, consider using an LM324, which contains four opamps in one package. For the high side of the range (10.5 to 12 V), a TL084 or a ‘rail-to-rail’ opamp like the TS924 is required. However, the TS924 cannot be used with supply voltages above 12 V.
Author: Raj. K. Gorkhali - Copyright: Elektor 2004
12 volt DC Power Supply from USB port
Description :
Using this circuit we can convert 5V DC from the computer USB port to 12V DC and a circuit like this will find a lot of application in USB powered systems. The heart of this circuit is IC LT1618 which is a constant current, constant voltage boost converter. The IC has a wide input voltage range of 1.8 to 18V DC and output voltage can be up to 35V DC.
In the circuit resistors R1, R2 sets the output voltage. Pin number 9 is the shutdown pin, less than 0.3V to this pin will shut down the IC. Pin number four is the current sense adjust pin. The current sense voltage can be reduced by applying a DC voltage to this pin. If this adjustment is not needed connect this pin to ground and you can omit components R3, R5 and Q1.
Circuit diagram of 12 volts dc power supply:
Circuit Diagram-12Volts DC power supply from USB port
Notes :
- C2 and C3 must be rated at least 15V.
- Less than 0.3V at the shutdown pin will shutdown the IC.
- Output voltage is governed by the following equation R1 = R2 ( (Vout /1.263V) -1).
Other Circuits Related to Power
Solar Panel Wiring Diagram Data Sheet
Solar Panel Wiring Diagram Data Sheet. OmniSite OEM Solar Module kits include a solar module and the OmniSite SWIL6 prewired voltage regulator with output cable. The OEM kits are supplied with a fixed tilt, 45° side-of-pole mount. The controller features a multi-function LED indicator and fuse protection. OmniSite single crystalline, high-efficiency solar modules are manufactured to exceed industry standards providing exceptional reliability and maximum power output. A twenty-year OEM warranty reflects the superior quality and assures long product life. The aluminum side-of-pole mounts include two clamps for nominal 2.5″ through 4″ poles (OD 2.875″ through 4.5″) and includes a 5 ft. cable.WARNING: For safety reasons, before hooking up wires, cover up the solar panel cells. A black trash bag works great for this. • Hook up the wires on the Sunsaver-6 Regulator in order by number, 1 thru 6. • For best results, face the panel due south at a 45 degree angle. • The main battery should sit on the bottom of the enclosure that houses the Sunsaver-6 regulator. • It will be necessary to drill one hole in the solar regulator enclosure for wiring purposes. • DO NOT plug in the backup small internal battery that comes with your OmniSiteRTU. Use only the large, external battery supplied with the solar panel unit.
Click here to Download Solar Panel Wiring Diagram Data Sheet
Friday, March 29, 2013
BMW E12 L Jetronic Fuel Injection Systems Schematic Diagram
The L-Jetronic System – Control Unit (ECU) takes sensor information such as AFM flow and temperature, Engine RPM (from ignition), Warm up information (from coolant temperature sensor), Throttle mode (idle and WOT switches), O2 sensor in Lambda systems. Then calculates opening duration of injectors. This ‘map’ is hardwired into system (there’s no chip available to modify).
Get detail information about BMW E12 L-Jetronic Fuel Injection Systems Schematic Diagram here – free download PDF file.
Four in One Burglar Alarm
In this circuit, the alarm will be switched on under the following four different conditions: 1. When light falls on LDR1 (at the entry to the premises). 2. When light falling on LDR2 is obstructed. 3. When door switches are opened or a wire is broken. 4. When a handle is touched. The light dependent resistor LDR1 should be placed in darkness near the door lock or handle etc. If an intruder flashes his torch, its light will fall on LDR1, reducing the voltage drop across it and so also the voltage applied to trigger 1 (pin 6) of IC1. Thus transistor T2 will get forward biased and relay RL1 energise and operate the alarm.
Sensitivity of LDR1 can be adjusted by varying preset VR1. LDR2 may be placed on one side of a corridor such that the beam of light from a light source always falls on it. When an intruder passes through the corridor, his shadow falls on LDR2. As a result voltage drop across LDR2 increases and pin 8 of IC1 goes low while output pin 9 of IC1 goes high. Transistor T2 gets switched on and the relay operates to set the alarm.
Four-in-One Burglar Alarm Circuit Diagram
The sensitivity of LDR2 can be adjusted by varying potentiometer VR2. A long but very thin wire may be connected between the points A and B or C and D across a window or a door. This long wire may even be used to lock or tie something. If anyone cuts or breaks this wire, the alarm will be switched on as pin 8 or 6 will go low. In place of the wire between points A and B or C and D door switches can be connected. These switches should be fixed on the door in such a way that when the door is closed the switch gets closed and when the door is open the switch remains open. If the switches or wire, are not used between these points, the points should be shorted. With the help of a wire, connect the touch point (P) with the handle of a door or some other suitable object made of conducting material. When one touches this handle or the other connected object, pin 6 of IC1 goes ‘low’.
So the alarm and the relay gets switched on. Remember that the object connected to this touch point should be well insulated from ground. For good touch action, potentiometer VR3 should be properly adjusted. If potentiometer VR3 tapping is held more towards ground, the alarm will get switched on even without touching. In such a situation, the tapping should be raised. But the tapping point should not be raised too much as the touch action would then vanish. When you vary potentiometer VR1, re-adjust the sensitivity of the touch point with the help of potentiometer VR3 properly. If the alarm has a voltage rating of other than 6V (more than 6V), or if it draws a high current (more than 150 mA), connect it through the relay points as shown by the dotted lines. As a burglar alarm, battery backup is necessary for this circuit. Note: Electric sparking in the vicinity of this circuit may cause false triggering of the circuit. To avoid this adjust potentiometer VR3 properly.
Source : http://www.ecircuitslab.com/2012/01/four-in-one-burglar-alarm.html
Rj61 Wiring Color Code Pinout Diagramcircuit Schematic
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Howstuffworks How Ethernet Works.
Rm4200d Ethernet Wiring Example3.
The Compass Derose Guide To Ethernet Computer Network Wiring.
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How To Make A Rj45 Cable Tester.
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Terminating Wall Plates Structured Home Wiring.
Thursday, March 28, 2013
Simple RF Detector For 2M
This simple circuit helps you sniff out RF radiation leaking from your transmitter, improper joints, a broken cable or equipment with poor RF shielding. The tester is designed for the 2-m amateur radio band (144-146 MHz in Europe). The instrument has a 4-step LED readout and an audible alarm for high radiation voltages. The RF signal is picked up by an antenna and made to resonate by C1-L1. After rectifying by diode D1, the signal is fed to a two-transistor high-gain Darlington amplifier, T2-T3.
Assuming that a 10-inch telescopic antenna is used, the RF level scale set up for the LEDs is as follows: When all LEDs light, the (optional) UM66 sound/melody generator chip (IC1) is also actuated and supplies an audible alarm. By changing the values of zener diodes D2, D4, D6 and D8, the step size and span of the instrument may be changed as required. For operation in other ham or PMR bands, simply change the resonant network C1-L1. As an example, a 5-watt handheld transceiver fitted with a half-wave telescopic antenna (G=3.5dBd), will produce an ERP (effective radiated power) of almost 10 watts and an e.m.f. of more than 8 volts close to your head.
Inductor L1 consists of 2.5 turns of 20SWG (approx. 1mm dia) enameled copper wire. The inside diameter is about 7mm and no core is used. The associated trimmer capacitor C1 is tuned for the highest number of LEDs to light at a relatively low fieldstrength put up by a 2-m transceiver transmitting at 145 MHz. The tester is powered by a 9-V battery and draws about 15mA when all LEDs are on. It should be enclosed in a metal case.
[Continue reading]
Assuming that a 10-inch telescopic antenna is used, the RF level scale set up for the LEDs is as follows: When all LEDs light, the (optional) UM66 sound/melody generator chip (IC1) is also actuated and supplies an audible alarm. By changing the values of zener diodes D2, D4, D6 and D8, the step size and span of the instrument may be changed as required. For operation in other ham or PMR bands, simply change the resonant network C1-L1. As an example, a 5-watt handheld transceiver fitted with a half-wave telescopic antenna (G=3.5dBd), will produce an ERP (effective radiated power) of almost 10 watts and an e.m.f. of more than 8 volts close to your head.Inductor L1 consists of 2.5 turns of 20SWG (approx. 1mm dia) enameled copper wire. The inside diameter is about 7mm and no core is used. The associated trimmer capacitor C1 is tuned for the highest number of LEDs to light at a relatively low fieldstrength put up by a 2-m transceiver transmitting at 145 MHz. The tester is powered by a 9-V battery and draws about 15mA when all LEDs are on. It should be enclosed in a metal case.
Thermostat Delay Relay Timer Circuit
The circuit given below describes a time delay relay system which is used for keeping a hot air blower working under a specifically programmed timing sequence. The idea was requested by Mr. Doug Shadix, lets learn more:
Hi Swagatam,
Looks like you know your stuff when it comes to these timer circuits, this one is a little out there but dont believe it is out of your knowledge.
This is a replacement part for an old Bryant furnace 822 relay. What is needed is a circuit that will get a 24VAC supply when the thermostat kicks in, it will have to have a 45 second delay before triggering a relay that powers the 1/3HP blower motor, the motor needs to run for 45 seconds after the voltage is shut off via the thermostat. Im sure that there is a more efficient circuit other than the 822 relay to do the job, especially when you take cost into the equation.
Once the thermostat kicks in it sends 24VAC thru the limit switch(as long as its not tripped from an overheat), then thru the pilot lights thermo coupler (providing that the pilot is lit)then applies it to the timer/relay. Once the thermostat kicks out the voltage goes to zero across all components.
Yes, the process would have to repeat each time the thermostat kicks the furnace on.
I was orginaly looking at the 556 timer chip to see if it would be able to serve the dual delay, but looking to you for the best way to get it done.
The Design:
The circuit shown below will respond exactly as per the requested specs. The entire functioning can be understood with the the following points:
When the thermostat "kicks in", the 24V AC is applied across D1 and ground of the circuit. The 24VAC gets rectified through D1/C1 and passes through R2 to reach the junction of R3 and D3.
Since initially C2 is in a discharged state the supply gets grounded via D3 and C2.
However as C2 starts charging up, after a predetermined time (45 seconds) set by the values of R2/C2, the voltage across C2 reaches about 1.4V which becomes sufficient to trigger T1.
T1 conducts and so does T2, pulling the relay into action.
The blower connected to the relay contacts initiates.
After some specified time the thermostat switches OFF.
When this happens, the voltage at the cathode of D1 becomes zero which makes D2 forward biased. such that The instantaneous voltage at the collector of T2 instantly passes via C3, D2 and retains the conduction of T1.
The above situation inhibits the circuit and the relay from switching OFF even after the thermostat has switched OFF.
However now C3 start charging up, and after some predetermined time (45 seconds) set by the value of C3/R6, it gets fully charged and shuts off the base bias to T1.....the circuit and the relay also shut off....until the thermostat "kicks back" again to repeat the procedure.
Parts List for the proposed timer delay/relay circuit idea
R1 = 100K
R2 = may be replaced with a 1M preset
R3,R4,R5 = 10K
R6 = may be replaced by a 100K preset
D1----D5 = 1N4007
C1,C2 = 100uF/50V
C3 = 220uF/25V
T1 = BC547
T2 = as per the relay coil current
Under Voltage Lockout for Buck Circuit Using LM2575
This is a implementation for buck boost configuration. This circuit is control by LM2575. This is the figure of the circuit.
In some applications it is desirable to keep the regulator off until the input voltage reaches a certain threshold. These circuits keep the regulator off until the input voltage reaches a predetermined level.
VTH ≈ VZ1 + 2VBE (Q1)
In some applications it is desirable to keep the regulator off until the input voltage reaches a certain threshold. These circuits keep the regulator off until the input voltage reaches a predetermined level.
VTH ≈ VZ1 + 2VBE (Q1)
1999 Chevrolet Chevy 1500 Pu V6 Wiring Diagram
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| 1999 Chevrolet Chevy 1500 Pu V6 Wiring Diagram |
The Part of 1999 chevrolet Chevy 1500 Pu V6 Wiring Diagram:power distribution coil, A/C compressor fuse, ignition fuse, underhood bussed electrical center, high pressure cutout switch, A/C compressor clutch, A/C low pressure cycling switch, ground distribution, powertrain control module, vehicle control module, A/C automatic recirculating switch, HVAC control module.
Wednesday, March 27, 2013
Kapanadze Free Energy Generator Schematics
Kapanadze Free Energy Generator Schematics
555 Equivalent Circuit
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