Published:2013/3/5 20:55:00 Author:Ecco | Keyword: TOUCH SWITCH , TOUCH ON-OFF
The Touch Switch circuit will detect stray voltages produced by mains voltages and electrostatic build-up in a room. In the first circuit, pin 2 must see a LOW for the circuit to activate. If sufficient static voltage is detected by the plate, the chip will change state. If not, you will need to touch the plate and the 0v rail. In the second circuit, two touch plates are provided and the resistance of your finger changes the voltage on pin 2 or 6 to toggle the 555.
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Published:2013/3/5 20:53:00 Author:Ecco | Keyword: TILT SWITCH
The output is LOW at start-up due to the capacitor on pin 4. When the mercury switch closes, the output goes HIGH and remains HIGH until the reset button is pressed. This circuit is called a LATCH.
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Published:2013/3/5 20:52:00 Author:Ecco | Keyword: STUN GUN
This circuit produces a very high voltage and care must be used to prevent getting a nasty shock.The transformer can produce over 1,000v and the 8-stage multiplier can produce up to 20,000v.
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Published:2013/3/5 20:50:00 Author:Ecco | Keyword: STEPPER MOTOR , CONTROLLER
The direction of rotation is determined by the FORWARD and REVERSE switches and the motor does not take any current when a switch is not pressed.
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Published:2013/3/5 20:46:00 Author:Ecco | Keyword: SIREN 100dB
This is a very loud siren and if two or more piezo's are located in a room, the burglar does not know where the sound is coming from. A robber will not stay anywhere with an ear-piercing sound as he cannot hear if someone is approaching. It's the best deterrent you can get. The F contact on the piezo is feedback and is not needed in this circuit.
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Published:2013/3/5 20:45:00 Author:Ecco | Keyword: SERVO TESTER
This circuit can be used to manually turn a servo clockwise and anti-clockwise. By pushing the forward or reverse button for a short period of time you can control the rotation of the servo. It will also test a servo. Here is a photo of a kit from Cana Kit for $10.00 plus postage (it is a slightly different circuit) and a motor and gearbox, commonly called a servo. The output shaft has a disk or wheel containing holes. A linkage or push-rod is fitted to a hole and when the disk rotates, the shaft is pushed and pulled. The shaft only rotates about 180?to actuate flaps or ailerons etc.
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Published:2013/3/5 20:39:00 Author:Ecco | Keyword: RAIN ALARM
This circuit consumes no current until moisture is detected on the rain plate.
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Published:2013/3/5 20:37:00 Author:Ecco | Keyword: POLICE SIREN
The Police Siren circuit uses two 555's to produce an up-down wailing sound. The first 555 is wired as a low-frequency oscillator to control the VOLTAGE CONTROL pin 5 of the second 555. The voltage shift on pin 5 causes the frequency of the second oscillator to rise and fall.
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Published:2013/3/5 0:45:00 Author:Ecco | Keyword: Non-contact, AC, measuring circuit
Non-contact AC measuring circuit is shown as figrue.
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Published:2013/3/4 3:12:00 Author:Ecco | Keyword: Photosensitive element, test circuit
Photosensitive element test circuit is shown as figure.
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Published:2013/3/5 0:43:00 Author:Ecco | Keyword: LED, parallel digital tube, static display , common anode
LED- parallel digital tube LED static display circuit (common anode) is shown as figure.
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Published:2013/3/5 0:42:00 Author:Ecco | Keyword: LED - serial, LED digital tube, dynamic scanning , display circuit , common anode
LED - serial LED digital tube dynamic scanning display circuit ( common anode ) is shown as figure.
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Published:2013/3/5 0:41:00 Author:Ecco | Keyword: LED - serial, LED digital tube , dynamic scanning , display circuit , common cathode
LED - serial LED digital tube dynamic scanning display circuit ( common cathode ) is shown as figure.
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Published:2013/3/5 0:33:00 Author:Ecco | Keyword: POLICE LIGHTS
This circuit uses a 555 timer which is setup to both runn in an Astable operating mode. This generates a continuous output via Pin 3 in the form of a square wave. When the timer's output changes to a high state this triggers the a cycle on the 4017 4017 decade counter telling it to output the next sequential output high. The outputs of the 4017 are connected to the LEDs turning them on and off.
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Published:2013/3/5 0:33:00 Author:Ecco | Keyword: MUSIC BOX
This circuit produces 10 different tones and by selecting suitable values to change the voltage on pin 5, the result can be quite pleasing. Note: the two unused outputs of the 4017 produce a tone equal to that produced by the 555 when pin 5 has no external control voltage.
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Published:2013/3/5 0:32:00 Author:Ecco | Keyword: MOTOR PWM
The speed of a motor can be adjusted by this circuit, from 5% to 95%.
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Published:2013/3/5 0:31:00 Author:Ecco | Keyword: MOSQUITO REPELLER
This circuit produces a tone above the human audible range and this is supposed to keep the mosquitoes away. You need a piezo diaphragm that will respond to 15kHz and these are very difficult to find.
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Published:2013/3/5 0:30:00 Author:Ecco | Keyword: MODEL RAILWAY, TIME Circuit
Here is a circuit that will convert any clock mechanism into Model Railway Time. For those who enjoy model railways, the ultimate is to have a fast clock to match the scale of the layout. This circuit will appear to make time fly by turning the seconds hand once every 6 seconds. The timing can be adjusted by changing the 47k. The electronics in the clock is disconnected from the coil and the circuit drives the coil directly. The circuit takes a lot more current than the original clock (1,000 times more) but this is one way to do the job without a sophisticated chip.
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Published:2013/3/5 0:27:00 Author:Ecco | Keyword: MACHINE GUN
This circuit produces a sound very similar to a machine gun:
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Published:2013/3/5 0:25:00 Author:Ecco | Keyword: LED DIMMER
This circuit will adjust the brightness of one or more LEDs from 5% to 95%.
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