A cinema installed mobile phone jammers

The newest Mobile Phone jammers make use of the 6 channel design which has solved the problems of signal unsteady or short amplifier distance, etc.
I want you to some common problems list in mobile phone jammers and method to solve these problems.Because of the widespread use of mobile phone, we noticed a lot of problems occur in the public, one of which is a noise. To stop the noise, caused by mobile phone, mobile phone jammers are placed in the public domain, theatre and cinema is one of them. Cell phone jammer is not a new thing, in the foreign actors, they used to complain that all mobile phone when watching this program.
Only in 2004, in France, a cinema installed mobile phone jammers, so the audience doesnt ring interrupted while enjoying the great movies from the mobile phone.
In 2007, an old theater, founded in 1756 in Russia decided to install and open mobile phone jammers when the display, because many people will not listen to rule without the use of mobile phone in the opera.The thing is, the theatre, the actors cant stand mobile phone. In the stage: nonsense, let me finish my words! It is very expensive to use the best 4g cell phone jammer in the theater, at that time, but all of a sudden stop interference to the actor, theater to spend so much money.According to the audience, because blockade of the wifi cell phone jammers for sale, the entire concert is really very quiet, no mobile phone ring tones in all. People in the enjoyment of opera, but many people are about people may try to contact them for some unexpected events.
A lot of people think it would be better if the theater, tell them about the use of mobile phone jammers, so they can make some arrangements with their friends and family. Most of the audience that the mobile phone jammers is really necessary in some high class of this concert.
But it did theater really use high-power radio interference when the display? Reporter talked about this a charger. He said they have built many devices in the beginning of the opera, mobile phone will have a great influence, so they use their mobile phone and portable cell phone jammers for sale stop the audience would not stop using their mobile phone."We just found no mobile phone signal, they are blocked?" recently, the audience will find a theater in Changzhou, when they are watching classical opera. Theres something to tell us, portable cell phone jammer 3g sale best will be open in some places like theaters and concert once a program to determine the quiet.
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Best Battery Charger Circuit Diagram

Best it mean UJT battry charger circuit diagram. This UJT battry charger circuit diagram will not work unless the battery to  be charged is connected with proper polarity. The  battery voltage controls the charger and when the  battery is fully charged, the charger will not supply  current to the battery. The battery charging the  current is obtained through the SCR when it is triggered  into the conducting state by the UJT relaxation  oscillator. 

The oscillator is only activated when the battery voltage is low. V8281 of the UJT is derived from the voltage of the battery to be charged, and since Vp= Vn= V8281 ; the higher V828` the higher Vp. When Vp exceeds the breakdown voltage of the zener diode Zl, the UJT will cease to fire and the SCR will not conduct. This indicates that the battery has attained its desired charge as set by R2.

UJT battry charger circuit diagram

Best Battery Charger Circuit Diagram


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UJT battry charger  diagram circuit
How to build a UJT battry charger circuit diagram
UJT battry charger Schametic diagrams
UJT battry charger circuits diagrams    
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How to Build a Electronic Telephone Ringer

How to Build a Electronic Telephone Ringer. This circuit produces a ringing sound similar to that made by more recent telephones. It consists of three almost identical oscillators connected in a chain, each generating a squarewave signal. The frequency of each oscillator depends on the RC combination: R4 and C1 around IC1.A, R8 and C2 around IC1.B and R12 and C3 around IC3.C.

The pairs of 100 kΩresistors divide the asym-metric power supply voltage (between 5 V and 30 V) so that, in conjunction with the 100 kΩfeedback resistors (R3, R7 and R11) either one third or two thirds of the supply voltage will be present at the non-inverting inputs to the opamps. The voltage across the capacitor therefore oscillates in a triangle wave between these two values.

Electronic Telephone Ringer Circuit Diagram:

Electronic Telephone Ringer-Circuit Diagram


The first oscillator is free-running at a frequency of approximately 1/3 Hz. Only when its output is high, and D1 stops conducting, can the second oscillator run. The frequency of the second oscillator is about 13 Hz, and optional LED D3 flashes when it is running. When the output of the second oscillator is low, the third is allowed to run. The frequency of the third oscillator is around 1 kHz, and this is the tone that is produced. The second oscillator is not absolutely necessary:

its function is just to add a little modulation to the 1 kHz tone. A piezo sounder is connected to the output of the third oscillator to convert the electrical signal into an acoustic one. The current consumption of the circuit is just under 1 mA with a 5V power supply, rising to about 1.65 mA with a supply volt-age of 15 V.


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Super High Power Portable TV and FM Jammer Circuit Diagram

This is the Super High Power Portable TV and FM Jammer Circuit Diagram. There are still neighbors that keep annoying you by having loud the TV or the radio? Well I have you the solution. In fact all neighborhood will face your jamming waves at their TVs and radios, so be careful. 

This Jammer is the improved version of the old `TV and FM jammer schematic` with the difference of much higher power. Many of you where asking for a stronger and wider effect but to be as portable as can be. Looking at the schematic you can see that, only the parts are changing keeping the basic circuit intact. Have in mind that this version needs heat sink and antenna to keep the transistor alive.

Super High Power Portable TV and FM Jammer Circuit Diagram

Super High Power Portable TV and FM Jammer Circuit Diagram



The power source comes from three 9 volt batteries in series, so we use 27 volts at input, and we get a power full 2,5 Watts at output.  
 
You are going to need 70cm to 2 meter simple wire antenna.  
 
As for the transistor Q its the 2N3553. Its a RF Power Silicon NPN Transistor in a TO39 type  package designed to be used in amplifiers and oscillator applications in military and industrial equipment.
  
Usually found as an output driver, or in predriver  stages in VHF equipment, but because here we dont care about the modulation of the signal but just the power, thats why we use it as a first and final output driver. 
The transistor is specified at 175MHz and 28V to give: Output Power: 2.5W, Minimum Gain: 10dB and Efficiency: 50%. 
 
The parts are: R1=10k, R2=2,2K, R3=100 C1=47uF/50V, C2=2.2nF, C3=10pF, SW=switch, B=Battery 9V. 
 
The coil L should be closely wound 5 turns (start tunning with the closely wound distance of turns and then play with it and the C4 capacitor, to find the desired frequency )of enameled copper wire 1.5mm and internal coil diameter of 1cm (leads 2x20mm). 
 
The variable capacitor C4 should be air trimmer capacitor rating 4 to 30 pf or the closest to this value. 
 
Connect the batteries in series place the best heat sink for TO39 case you can get and pack it all in a small plastic box. Enjoy ;)




Datasheet file1: Click here to download 2n3553 datasheet.
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Build a Positive And Negative Voltage Switching Supply

Build a Positive And Negative Voltage Switching Supply. An LT1172 generates positive and negative voltages from a 5-V input. The LT1172 is configured as a step-up converter. To generate the negative output, a charge pump is used. C2 is charged by the inductor when D2 is forward-biased and discharges into C4 when LT1172`s power switch pulls the positive side of C2 to ground. 

 Positive And Negative Voltage Switching Supply  Circuit Diagram

 Positive And Negative Voltage Switching Supply  Circuit Diagram
 
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Automotive LED Timing Light

A useful timing strobe can be constructed using high-brightness LEDs and a few common components. Ignition pulses from the number 1 cylinder high-tension lead are used to trigger the circuit via a home-made inductive pickup. Transistors Q1 & Q2 buffer and amplify the pulses from the pickup, which then drive the inputs of three Schmitt-trigger inverters (IC1a, IC1c & IC1f). Each positive pulse at the inverter inputs causes a low pulse at their outputs, forward-biasing D2 and immediately discharging the 6.8nF capacitor. When the capacitor is discharged, the inputs of the second bank of three inverters (IC1b, IC1d & IC1e) see a logic low level, so their outputs go high, driving Q3 into conduction and powering the LED array. After the pulse ends, the IC1a, IC1c & IC1f inverter outputs return high, reverse biasing D2.

Automotive LED timing light circuit schematic

However, it takes some time for the 6.8nF capacitor to charge to the logic high threshold voltage of the inverters’ inputs, effectively stretching the initial pulse width and lighting the LEDs for the required amount of time. The pickup can be salvaged from an old Xenon timing light or made up from a "C" type ferrite or powered iron core large enough to fit around a HT lead. Some experimentation will be required to determine the number of turns required to achieve reliable triggering. About 100 turns of light-gauge wire proved sufficient on the prototype. A cleat is used to close the magnetic path around the lead and is held in place with a large battery clip. Miniature screened microphone cable can be used to connect the pickup to the circuit, to prevent interference from other sources.
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12 Volt Battery Guardian

Dont get caught with a flat battery; this easy-to-build circuit can cut off the power to a 12V fridge or car stereo system if the battery voltages drops below critical level. Electric fridges in vans and 4WDs are a great idea but if you are not careful, they can severely discharge the battery and leave you stranded. Maybe the battery will end up with severe damage as well. The same problem applies if you have a big stereo system and you like to play it without the motor running.


Main features:
  • Cuts power to load (eg, fridge) when battery voltage drops below a preset level.
  • 10A rating.
  • Low power drain.
  • Chirping sound during cut-out.
  • Flashing LED indication during cut-out.
  • Automatically reconnects power when battery recharged.
Operation on 12V is fine when the motor is running and battery charge is maintained but if the fridge is allowed to run for too long when the motor is stopped, it can flatten the battery in a relatively short time. This is where the Battery Guardian comes into play. It monitors the battery voltage and disconnects power to the fridge before the battery becomes too flat to allow the engine to be started again.

Parts layout:



PCB layout:


Circuit diagram:




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1W BTL Audio Amplifier

The TDA8581(T) from Philips Semiconductors is a 1-watt Bridge Tied Load (BTL) audio power amplifier capable of delivering 1 watt output power into an 8-Wload at THD (total harmonic distortion) of 10% and using a 5V power supply. The schematic shown here combines the functional diagram of the TDA8551 with its typical application circuit. The gain of the amplifier can be set by the digital volume control input. At the highest volume setting, the gain is 20 dB. Using the MODE pin the device can be switched to one of three modes: standby (MODE level between Vp and Vp–0.5 V), muted (MODE level between 1 V and Vp–1.4 V) or normal (MODE level less than 0.5 V). The TDA8551 is protected by an internal thermal shutdown protection mechanism. The total voltage loss for both MOS transistors in the complementary output stage is less than 1 V.

Circuit diagram:1-Watt BTL audio amplifierUsing a 5-V supply and an 8-W loudspeaker, an output power of 1 watt can be delivered. The volume control has an attenuation range of between 0 dB and 80 dB in 64 steps set by the 3-state level at the UP/DOWN pin: floating: volume remains unchanged; negative pulses: decrease volume; positive pulses: increase volume Each pulse at he Up/DOWN pin causes a change in gain of 80/64 = 1.25 dB (typical value). When the supply voltage is first connected, the attenuator is set to 40 dB (low volume), so the gain of the total amplifier is then –20 dB. Some positive pulses have to be applied to the UP/DOWN pin to achieve listening volume. The graph shows the THD as a function of output power. The maximum quiescent current consumption of the amplifier is specified at 10mA, to which should be added the current resulting from the output offset voltage divided by the load impedance.
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Safe Oscillator For Watch Crystals

This circuit was developed to allow watch crystals to be used in an existing CMOS oscillator circuit that was to run from a 12V supply. The problem is that these crystals only work up to a supply voltage of about 6V. Any more than that and the crystal will be over-driven, causing it to shatter. This circuit solves the problem by using LEDs 1 & 2 and a 470nF capacitor (C3) to limit the drive to the crystal to about 4V peak-to-peak. Note that it may be necessary to adjust C1 & C2 to ensure reliable start-up and stable oscillation with some crystals. However, the C1:C2 ratio should be maintained. As a bonus, the two LEDs both glow, giving a visual indication that the oscillator is working.

Safe oscillator for watch crystals circuit schematic

Editors note:
The relatively high values used here for capacitors C1 & C2 will load the crystal, which means that the oscillator will run at less than the nominal crystal frequency (32.768kHz).
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Battery Charging Indicator For Mains Adaptor

Although you may well be the proud owner of the very latest NiCd battery charger, you may still come across the odd incompatible battery, for example, one having a rare voltage or requiring a much higher charging current than can be supplied by your off-the-shelf charger. In these cases, many of you will resort to an adjustable mains adaptor (say, a 500-mA type) because that is probably the cheapest way of providing the direct voltage required to charge the battery. Not fast and not very efficient, this rustic charging system works, although subject to the following restrictions:


  1. You should have some idea of the charging current. In case you use an adaptor which is adjustable but of the unregulated, low output current type, you can adjust the current by adjusting the output voltage.
  2. You have to know if the current actually flows through the battery. A current-detecting indicator is therefore much to be preferred over a voltage indicator.
  3. To prevent you from forgetting all about the charging cycle, the indicator should be visible from wherever you pass by frequently. Using the circuit shown here, the LED lights when the baseemitter potential of the transistor exceeds about 0.2 V. Using a resistor of 1 ? as suggested this happens at a current of about 200 mA, or about 40 mA if R1 is changed to 4.7?. The voltage drop caused by this indicator can never exceed the base-emitter voltage (UBE) of the transistor, or about 0.7V. Even if the current through R1 continues to increase beyond the level at which UBE = 0.7 V, the base of the transistor will absorb the excess current. The TO-220 style BU406 transistor suggested here is capable of accepting base currents up to 4A. Using this charging indicator you have overcome the restrictions 2 and 3 mentioned above.
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Luggage Security System

While traveling by a train or bus, we generally lock our luggage using a chain-and-lock arrangement. But, still we are under tension, apprehending that somebody may cut the chain and steal our luggage. Here is a simple circuit to alarm you when somebody tries to cut the chain. Transistor T1 enables supply to the sound generator chip when the base current starts flowing through t. When the wire (thin enameled copper wire of 30 to 40 SWG, used or winding transformers) loop around the chain is broken by somebody, the base of transistor T1, which was earlier tied to positive rail, gets opened. As a result, transistor T1 gets forward biased to extend the positive supply to the alarm circuit. In idle mode, the power consumption of the circuit is minimum and thus it can be used for hundreds of travel hours. To enable generation of different alarm sounds, connections to pin 1 and 6 may be made as per the table.

Luggage Security System Circuit Diagram
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Two Basic Motor Speed Controllers

Here are two simple 12V DC motor speed controllers that can be built for just a few dollars. They exploit the fact that the rotational speed of a DC motor is directly proportional to the mean value of its supply voltage. The first circuit shows how variable voltage speed control can be obtained via a potentiometer (VR1) and compound emitter follower (Q1 & Q2). With this arrangement, the motor’s DC voltage can be varied from 0V to about 12V. This type of circuit gives good speed control and self-regulation at medium to high speeds but very poor low-speed control and slow starts. The second circuit uses a switchmode technique to vary motor speed.

Two basic motor speed controllers circuit schematic
Fig.1: a very simple motor speed controller based on a compound emitter follower (Q1 & Q2).

Here a quad NOR gate (IC1) acts as a 50Hz astable multivibrator that generates a rectangular output. The mark-space ratio of the rectangular waveform is fully variable from 20:1 to 1:20 via potentiometer VR1. The output from the multivibrator drives the base of Q1, which in turn drives Q2 and the motor. The motor’s mean supply voltage (integrated over a 50Hz period) is thus fully variable with VR1 but is applied in the form of high-energy "pulses" with peak values of about 12V.

Two basic motor speed controllers circuit schematic
Fig.2: this slightly more complicated circuit gives better low speed control and higher torque.

This type of circuit gives excellent full-range speed control and gives high motor torque, even at very low speeds. Its degree of speed self-regulation is proportional to the mean value of the applied voltage. Note that for most applications, the power transistor (Q2) in both circuits will need to be mounted on an appropriate heatsink.
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Alarm Clock With Day Selector

This  circuit disables an alarm clock on Saturdays and Sundays when people like to sleep in but enables normal operation on Mondays to Fridays so that people rise in time for work or school. The core of the circuit is a 4017 decade counter which acts as the day counter and it is used in conjunction with a desk clock which acts the alarm and a watch module with alarm function which provides one clock pulse very day to the 4017. In operation, the watch module feeds a day pulse via transistor Q3 to the clock input of IC1. This has seven outputs connected via day switches (S1-S7) and diodes D3-D9 to Q1 which disables the alarm signal to the speaker via transistor Q2. LEDs1-7 indicate the actual day (if you forget!).

Circuit diagram:

Alarm-clock-with-day Selector Circuit Diagram

Alarm Clock With Day Selector Circuit Diagram

To set the system, set the desk clock for the correct time and for the desired alarm time (eg, 6’o’clock). The watch module is set to the correct time and its alarm set to midnight. The day counter, IC1, is set to the correct day, as indicated by the LEDs, by pushing switch S12 and closing switch S8 or S9. S8 is normally left open to conserve the battery by leaving the LEDs off. As shown on the circuit, switches S1-S7 are set to sound the alarm on Mondays to Fridays and disable it on Saturday and Sunday. However, you can change the days to suit your work habits.

Author: Rasim Kucalovic - Copyright: Silicon Chip Electronics

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Park Aid Modification Circuit

Three-step beeps signal bumper-barrier distance, Infra-red operation, indoor use

This modification was designed on request: some people prefer an audible alert instead of looking at the LED display, making easier the parking operation. The original Park-aid circuit was retained, but please note that the input pins of IC2B, IC2C and IC2D are reversed. LEDs D5, D6 and D7, as also resistors R12, R13 and R14 are omitted. IC2B, IC2C and IC2D outputs drive resistors R15, R16 and R17 through D8, D9 and D10 respectively, in order to change the time constant of a low frequency oscillator based on the 555 timer IC4. This allows the Piezo sounder to start beeping at about 2 times per second when bumper-wall distance is about 20 cm., then to increase the beeps to about 3 per second when bumper-wall distance is about 10 cm. and finally to increase further the beeps frequency to more than 4 beeps per second when the distance is about 6 cm. or less.

Circuit diagram:

Park-Aid Modification Circuit Diagram

Park-Aid Modification Circuit Diagram

Parts:

R15_____________3K3 1/4W Resistor
R16___________330K 1/4W Resistor
R17___________470K 1/4W Resistor
R18___________150K 1/4W Resistor
C6______________1µF 63V Electrolytic or Polyester Capacitor
D8,D9,D10____1N4148 75V 150mA Diodes
IC4_____________555 Timer IC
BZ1___________Piezo sounder (incorporating 3KHz oscillator)

Source : www.redcircuits.com

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555 Timer With Variable On Off Times

This circuit enables the on/off times of a 555 timer to be independently varied over a wide range. This is not possible with a conventional 555 circuit with the RC network being charged from the positive supply rail and discharged via pin 7. Instead, the capacitor at pins 2 & 6 of IC1 is charged and discharged from the output at pin 3. Furthermore, the charging and discharging circuits are different, being isolated by diodes D1 & D2.

555 Timer Circuit With Variable On/Off Times circuit schematic

Therefore the capacitor at pins 2 & 6 is charged via diode D2 and trimpot VR2 and discharged via D1 and trimpot VR1. With this arrangement you can have very long on times combined with very short off times and vice versa, or you can adjust the duty cycle to exactly 50% and so on. This circuit also employs a second 555 timer (IC2) as an inverter so that complementary pulses are available, if required. If not, delete IC2.
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Fuse Box BMW R1150RT 2002 Diagram

Fuse Box BMW R1150RT 2002 Diagram - Here are new post for Fuse Box BMW R1150RT 2002 Diagram.

Fuse Box BMW R1150RT 2002 Diagram



Fuse Box BMW R1150RT 2002 Diagram
Fuse Box BMW R1150RT 2002 Diagram

Fuse Panel Layout Diagram Parts: instrument cluster, telltale light, revolution counter, indicator clamping, windscreen adjuster, parking light, tail light, windscreen adjuster, power socket, radio, horn, motronic control unit, motronic relay, diagnosis connector, fuel pump relay, oxygen sensor, heated handlebar grips, radio, fog lamp relay.
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Build a 16 LED Chaser Circuit Diagram

This 16 LED Chaser Circuit Diagram is a double direction flash. Similar to Digital Ping- Pong 1, there is a movement of a lit dot, up and down along the LEDs length.

16 LED Chaser Circuit Diagram

16 LED Chaser Circuit Diagram


When the D16 lit the situation changes and there is a reverse movement. Lit D15-14 ……D16, is lit making circles when the circuit is under power. The IC1 is an unstable flip- flop supplying with stable frequency pulses (the frequency can be changed by TR1, adjusting the velocity of the LEDs up and down).

This frequency supplies the IC3 (which is a 4-Bit UP and DOWN counter) through 2 gates A-B of the IC2. The output counter supplies the IC4 that is the driver of the LEDs. The parts C- D of The IC2, make a R-S flip- flop, that changes situation, when the edge LEDs D1 and D16 lit.

We have an electronic limit for the situation change. In proportion the shape we make with the LEDs, we can have the proportionate optional result, making various effects.

Part List

R1= 100Kohms
R2= 220Kohms
R3= 470 ohms
TR1= 1Mohms
C1= 330nF 100V MKT
D1-16= LED 5mm
IC1= 555
IC2= 7400
IC3= 74193
IC4= 74154
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3 Transistor Audio Amplifier Circuit

Description
Here is a little audio amplifier similar to what you might find in a small transistor radio. The input stage is biased so that the supply voltage is divided equally across the two complimentary output transistors which are slightly biased in conduction by the diodes between the bases. A 3.3 ohm resistor is used in series with the emitters of the output transistors to stabilize the bias current so it doesnt change much with temperature or with different transistors and diodes. As the bias current increases, the voltage between the emitter and base decreases, thus reducing the conduction.
Input impedance is about 500 ohms and voltage gain is about 5 with an 8 ohm speaker attached. The voltage swing on the speaker is about 2 volts without distorting and power output is in the 50 milliwatt range. A higher supply voltage and the addition of heat sinks to the output transistors would provide more power. Circuit draws about 30 milliamps from a 9 volt supply. 
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Mobile Cellphone Battery Charger Circuit

Charging of the mobile phone, cellphone battery is a big problem while traveling as power supply source is not generally accessible. If you keep your cellphone switched on continuously, its battery will go flat within five to six hours, making the cellphone useless.

A fully charged battery becomes necessary especially when your distance from the nearest relay station increases. Here’s a simple charger that replenishes the cellphone battery within two to three hours. Basically, the charger is a current-limited voltage source. Generally, cellphone battery packs require 3.6-6V DC and 180-200mA current for charging. These usually contain three NiCd cells, each having 1.2V rating.

Current of 100mA is sufficient for charging the cellphone battery at a slow rate. A 12V battery containing eight pen cells gives sufficient current (1.8A) to charge the battery connected across the output terminals. The circuit also monitors the voltage level of the battery. It automatically cuts off the charging process when its output terminal voltage increases above the predetermined voltage level.
Circuit Diagram:
Parts
  • P1 = 20K
  • P2 = 20K
  • R1 = 390R
  • R2 = 680R
  • R3 = 39R-1W
  • R4 = 27K
  • R5 = 47K
  • R6 = 3.3K
  • R7 = 100R-1W
  • C1 = 4.7uF-25V
  • C2 = 0.01uF
  • C3 = 0.001uF
  • D1 = 5.6V-1W Zener
  • D2 = 3mm. Red LED
  • Q1 = SL100
  • S1 = On/Off Switch
  • B1 = 1.5vx8 AA Cells in Series
  • IC1 = NE555 Timer IC 
Circuit Operation
Timer IC NE555 is used to charge and monitor the voltage level in the battery. Control voltage pin 5 of IC1 is provided with a reference voltage of 5.6V by zener diode D1. Threshold pin 6 is supplied with a voltage set by P1 and trigger pin 2 is supplied with a voltage set by P2. When the discharged cellphone battery is connected to the circuit, the voltage given to trigger pin 2 of IC1 is below 1/3Vcc and hence the flip-flop in the IC is switched on to take output pin 3 high. When the battery is fully charged, the output terminal voltage increases the voltage at pin 2 of IC1 above the trigger point threshold.
This switches off the flip-flop and the output goes low to terminate the charging process. Threshold pin 6 of IC1 is referenced at 2/3Vcc set by P1. Transistor Q1 is used to enhance the charging current. Value of R3 is critical in providing the required current for charging. With the given value of 39-ohm the charging current is around 180 mA. The circuit can be constructed on a small general-purpose PCB.
For calibration of cut-off voltage level, use a variable DC power source. Connect the output terminals of the circuit to the variable power supply set at 7V. Adjust P1 in the middle position and slowly adjust P2 until LED (D2) goes off, indicating low output. LED should turn on when the voltage of the variable power supply reduces below 5V. Enclose the circuit in a small plastic case and use suitable connector for connecting to the cellphone battery.
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Hand Held Transceiver dc Adapter Circuit Diagram

This Hand Held Transceiver dc Adapter Circuit Diagram provides a regulated 9-V source for operating a Kenwood TR-2500 hand-held transceiver in the car. The LM317T`s mounting tab is electrically connected to its output pin, so take this into account as you construct your version of the adapter. The LM317T regulator dissipates 2 or 3 W in this application, so mount it on a 1-x -2-inch piece of `is-inch-thick aluminum heatsink. 

 Hand Held Transceiver dc Adapter Circuit Diagram

Hand Held Transceiver dc Adapter Circuit Diagram

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Simple Adjustable Notch Filter Circuit Diagram

Adjustable Notch Filter Circuit Diagram. In applications where the rejected signal might deviate slightly from the null on the notch network, it is advantageous to lower the Q of the network. This insures some rejection over a wider range of input frequencies. The figure shows a circuit where the Q may be varied from 0.3 to 50. A fraction of the output is fed back to R3 and C3 by a second voltage follower, and the notch Q is dependent on the amount of signal fed back. A second follower is necessary to drive the twin `T` from a low-resistance source so that the notch frequency and depth will not change with the potentiometer setting.

Adjustable Notch Filter Circuit Diagram


 
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Building Electric Guitarwiring Electronics

Guitar Wiring on Electric Guitar Wiring   Watch That Flying Solder
Electric Guitar Wiring Watch That Flying Solder.


Guitar Wiring on Wiring Page
Wiring Page.


Guitar Wiring on Typical Strat Three Pickup Wiring  The Switch Is Usually Installed
Typical Strat Three Pickup Wiring The Switch Is Usually Installed.


Guitar Wiring on Pickup Blend Pot Guitar Wiring
Pickup Blend Pot Guitar Wiring.


Guitar Wiring on Gibson    50s Wiring On A Stratocaster   Premier Guitar
Gibson 50s Wiring On A Stratocaster Premier Guitar.


Guitar Wiring on Source   Http   Www Seymourduncan Com Support Wiring Diagrams
Source Http Www Seymourduncan Com Support Wiring Diagrams.


Guitar Wiring on Capacitor Wiring
Capacitor Wiring.


Guitar Wiring on Ibanez Guitar Wiring Diagram
Ibanez Guitar Wiring Diagram.


Guitar Wiring on Stratocaster Wiring Harness
Stratocaster Wiring Harness.


Guitar Wiring on Building Electric Guitar   Wiring The Electronics
Building Electric Guitar Wiring The Electronics.


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Flashing LED Battery status Indicator

Signals when an on-circuit battery is exhausted 5V to 12V operating voltage
A Battery-status Indicator circuit can be useful, mainly to monitor portable Test-gear instruments and similar devices. LED D1 flashes to attire the users attention, signaling that the circuit is running, so it will not be left on by mistake. The circuit generates about two LED flashes per second, but the mean current drawing will be about 200µA. Transistors Q1 and Q2 are wired as an uncommon complementary astable multivibrator: both are off 99% of the time, saturating only when the LED illuminates, thus contributing to keep very low current consumption. 

Circuit diagram :
Flashing-LED Battery
Flashing-LED Battery-status Indicator Circuit Diagram

The circuit will work with battery supply voltages in the 5 - 12V range and the LED flashing can be stopped at the desired battery voltage (comprised in the 4.8 - 9V value) by adjusting Trimmer R4. This range can be modified by changing R3 and/or R4 value slightly.

When the battery voltage approaches the exhausting value, the LED flashing frequency will fall suddenly to alert the user. Obviously, when the battery voltage has fallen below this value, the LED will remain permanently off. To keep stable the exhausting voltage value, diode D1 was added to compensate Q1 Base-Emitter junction changes in temperature. The use of a Schottky-barrier device (e.g. BAT46, 1N5819 and the like) for D1 is mandatory: the circuit will not work if a common silicon diode like the 1N4148 is used in its place.

Parts :
R1,R7__________220R  1/4W Resistors
R2_____________120K  1/4W Resistor
R3_______________5K6 1/4W Resistor
R4_______________5K  1/2W Trimmer Cermet or Carbon
R5______________33K  1/4W Resistor
R6_____________680K  1/4W Resistor
R8_____________100K  1/4W Resistor
R9_____________180R  1/4W Resistor
C1,C2____________4µ7  25V Electrolytic Capacitors
D1____________BAT46  100V 150mA Schottky-barrier Diode
D2______________LED  Red 5mm.
Q1____________BC547   45V 100mA NPN Transistor
Q2____________BC557   45V 100mA PNP Transistor
B1_______________5V to 12V Battery supply
Notes :
  • Mean current drawing of the circuit can be reduced further on by raising R1, R7 and R9 values.


Streampowers
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Tracking Dual Output Bipolar Supply Circuit Diagram

This Tracking Dual Output Bipolar Supply Circuit Diagram is useful for a bench supply in the lab. Separate or tracking operation is possible. The regulators should be properly heatsinked. Tl is a 24-Vac wall transformer of suitable current capacity. 

Tracking Dual Output Bipolar Supply Circuit Diagram 

Tracking Dual Output Bipolar Supply Circuit Diagram

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How to make an electric magnet

]

Then turn the coil around the nail but before turning the coil cover the nail with a peace of paper.Then attach every thing according to the following circuit.finally give the power and close it to the metal dust then you can see they stick to the nail..# Now you know how to make an electric magnet

# As your second project make an electric bell
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Fuse Box BMW 328i 1999 Engine Compartment Diagram

Fuse Box BMW 328i 1999 Engine Compartment Diagram - Here are new post for Fuse Box BMW 328i 1999 Engine Compartment Diagram.

Fuse Box BMW 328i 1999 Engine Compartment Diagram



Fuse Box BMW 328i 1999 Engine Compartment Diagram
Fuse Box BMW 328i 1999 Engine Compartment Diagram

Fuse Panel Layout Diagram Parts: inside mirror electrochromic, interior light, light module, make up mirror light, navigation, on board computer, outside mirror, parking aid, passenger compartment, radio, rain sensor, rear wiper, roler sun blind, secondary air pump, side airbag, socket, speed control, starter interlock, telephone, trailer coupling, window lift, windscreen washer.
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1 W Home Stereo Amplifier Rise

This is a one watt home stereo amplifier module project using the KA2209 IC from Samsung, which is equivalent to the TDA2822. It operates from 3-12V DC & will work from a battery since the dormant current drain is low. It requires no heat sink for normal use. The input & output are both ground referenced. Maximum output will be obtained with a 12V power supply & 8 ohm speaker, however it is suitable for driving headphones from a supply as low as 3V.

The Specifications of the home stereo amplifier :

D.C. input : 3 – 12 V at 200 – 500 mA max
Idle current : approx. 10 mA
Power output : > 1 Watt max. 4-8 ohms, 12V DC
Freq. Resp. : approx. 40 Hz to 200 kHz, 8 ohm, G=10
THD : < 1 % @ 750 mW, 4-8 ohm, 12V
Gain : approx. x10 (20 dB) OR x100 (40dB)
S/N ratio : > 80 dB, G = 20 dB
Sensitivity : < 300 mV, G = 20 dB
Input Impedance : approx. 10 k ohm

Description 

The gain is adjustable from ten to 100, i.e. twenty to 40 dB. Start with feedback resistors R1 and R3 of 1k ohm, this will give a gain of ten which ought to be adequate for most applications. In case you need more gain, you can remove resistors R1 and R3.This will give a gain of about 100, or 40 dB.The input attenuation can be adjusted by the potentiometer which can be used as a volume control. The IC gain ought to be kept as low as necessary to accomplish full output, with the in put potentiometer and your signal source at maximum.


Voltage Gain = 1+ R1/R2 = 1+R3/R4, however the maximum gain with no outside feedback is about 100, or 40dB. (GdB = 20log Gv)

This will keep the signal to noise ratio as high as feasible. Additional gain provided by the amplifier will reduce the S/N ratio by a similar amount, since the input noise figure is constant. Other values for R1 and R3 of between 1k and 10k ohm can be used if an intermediate gain level is necessary.

If driving a pair of headphones, you may also need a 100 ohm resistor in series with each output to reduce the output level, depending on headphone impedance & sensitivity. Make positive you start with the volume right down to check. Numerous headphones may be driven from the amplifier in the event you wish, since most headphones have at least 16 ohm impedance, or more often 32 ohm.

There are only a few outside parts, the IC contains most of the necessary circuitry. R1,R2 and R3,R4 are the feedback resistors. C1 provides power supply decoupling. C2 and C3 are the input coupling capacitors, which block any DC that might-be present on the inputs. C4,C5 block DC in the feed back circuit from the inverting inputs, and C6,C7 are the output coupling capacitors. C8, R5 and C9,R6 act as Nobel networks providing a high frequency load to maintain stability at frequencies where loud speaker inductive reactant may become excessive. The pot provides adjustable input level attenuation.


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Build a Room Ioniser Circuit Diagram

This is a voltage multiplier circuit acting as an Room Ioniser Circuit Diagram. Its calculated to feed 220V from mains and the output is about 6KV. Caution should take with the circuit as can be dangerous due to mains. You can place a needle at the output 3cm long. Even you disconnect from mains, capacitors can be dangerous so make sure to discharge them by shorting their pins before you touch the circuit with hands.

Room Ioniser Circuit Diagram

Build a Room Ioniser Circuit Diagram
 
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Radio Metal Detector

This metal detector circuit diagram is designed using on a transistor radio as an detector. L1 search coil of the metal detector must have 18 turns from a 0.65 mm enameled wire scrambled on a 4 inch diameter support . The C1 capacitor is a variable capacitor with a value of 365 pF, C2 is a 100pF silver mica capacitor , C3 is a 0.05 uF disc capacitor and the C4 is a 4.7 uF capacitor .

Radio Metal Detector Circuit diagram


The Q1 transistor can be RCA SK3011 npn transistor or equivalent type and all resistors need to be ½ watts . With the radio tuned to a weak station you must adjust the variable capacitor C1 until the locator oscillator beats against the received signal. If a metal is detected the inductance of the L1 coil is changed, changing the frequency of the locator oscillator’s, resulting a change in the beat tone radio .
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switch mode power supply circuits

switch mode power supply circuits
Transformerless Power Supply CircuitIf you are not accomplished in ambidextrous with it, again leave this activity alone.Although Mains accessories can itself absorb a lot of current, the circuits we body to ascendancy it, usually alone crave a few milliamps. Yet the low voltage ability accumulation is frequently the better allotment of the...



If you are not accomplished in ambidextrous with it, again leave this activity alone.Although Mains accessories can itself absorb a lot of current, the circuits we body to ascendancy it, usually alone crave a few milliamps. Yet the low voltage ability accumulation is frequently the better allotment of the architecture and a abundant allocation of the cost.
This ambit will accumulation up to about 20ma at 12 volts. It uses capacitive reactance instead of resistance; and it doesnt accomplish actual abundant heat.The ambit draws about 30ma AC. Always use a agglutinate and/or a aqueous resistor to be on the safe side. The ethics accustomed are alone a guide. There should be added than abundant ability accessible for timers, ablaze operated switches, temperature controllers etc, provided that you use an optical isolator as your circuits achievement device.

MOC 3010/3020) If a broadcast is unavoidable, use one with a mains voltage braid and about-face the braid application the optical isolator.C1 should be of the suppressor type; fabricated to be affiliated anon beyond the admission Mains Supply. They are about covered with the logos of several altered Safety Standards Authorities. If you charge added current, use a beyond amount capacitor; or put two in parallel; but be accurate of what you are accomplishing to the Watts. The low voltage AC is supplied by ZD1 and ZD2.
The arch rectifier can be any of the baby Round, In-line, or DIL types; or you could use four abstracted diodes. If you appetite to, you can adapt R2 and ZD3 with a 78 Series regulator. The abounding sized ones will work; but if amplitude is tight, there are some baby 100ma versions accessible in TO 92 blazon cases. They attending like a BC 547. It is additionally account acquainted that abounding baby circuits will assignment with an able supply. You can, of course, adapt any or all of the Zenner diodes in adjustment to aftermath a altered achievement voltage. As for the mains voltage, the advancement apropos the 110v adaptation is aloof that, a suggestion. I havent congenital it, so be able to agreement a little.

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Nokia X2 00 Mic solution guide

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Wiring Diagram

Wiring Diagram on Rsx Automatic Interlock System Wiring Diagram   Circuit Schematic
Rsx Automatic Interlock System Wiring Diagram Circuit Schematic.


Wiring Diagram on 2002 Mazda Protege Hvac System Wiring Diagram   Circuit Schematic
2002 Mazda Protege Hvac System Wiring Diagram Circuit Schematic.


Wiring Diagram on Typical Wiring Diagram
Typical Wiring Diagram.


Wiring Diagram on Series 600 Electric Wiring Diagram   Car Parts And Wiring Diagram
Series 600 Electric Wiring Diagram Car Parts And Wiring Diagram.


Wiring Diagram on The Following Schematic Shows Typical Wiring Diagram Of The 1999
The Following Schematic Shows Typical Wiring Diagram Of The 1999.


Wiring Diagram on Wiring Diagram
Wiring Diagram.


Wiring Diagram on Wiring Diagram
Wiring Diagram.


Wiring Diagram on Wiring Diagram
Wiring Diagram.


Wiring Diagram on Wiring Diagrams    Auspex Creative Flow Australia
Wiring Diagrams Auspex Creative Flow Australia.


Wiring Diagram on Outdoor Lighting Wiring Diagram   2 Gang Switch
Outdoor Lighting Wiring Diagram 2 Gang Switch.


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