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Electrical Equipment Circuit

Index 4

Great Wall programmed box fan circuit

Published:2012-11-20 20:34:00 Author:Ecco | Keyword: Great Wall , programmed box fan

Great Wall programmed box fan circuit
Great Wall FS36-40 fan uses programmable technology, and it has three wind species, three wind speeds and four-time segment timing shutdown function. It also has 10W lights at night, and the circuit is shown as the figure. The circuit uses IC chip RTS-1A with fewer external components and manual operation and automatic operation. H1 ~ H10 are light emitting diodes.   (View)

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Homemade fast hand dryer circuit

Published:2012-11-20 1:27:00 Author:Ecco | Keyword: Homemade, fast hand dryer

Homemade fast hand dryer circuit
Homemade fast hand dryer circuit
Homemade fast hand dryer circuit
Homemade fast hand dryer circuit

When it is illuminated, the IC's pin 1 is in high potential, TWH8751 is cutoff, J loses power, J1-1 disconnects. When the hand gets into and blocks the light, D2 shows a large resistance, pin 2 of the IC is in a low potential, the IC output end gets conduction, J1-1 is turned on, the electric wire and the motor are energized.   (View)

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Computer Microphone

Published:2012-11-19 21:41:00 Author:muriel | Keyword: Computer Microphone

Computer Microphone
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High Power FM Wireless Microphone

Published:2012-11-14 0:55:00 Author:muriel | Keyword: High Power , FM , Wireless, Microphone

High Power FM Wireless Microphone
This FM Wireless Microphone has been a very popular project with beginners and experienced constructors alike. It has been used inside guitars and as the basis of a remote control system. I do however, receive many requests for a higher powered circuit and better microphone sensitivity. This High Power FM Wireless Microphone has a better frequency stability, over 1 Km range and is good on microphone sensitivity. This has been achieved by adding an RF amplifier buffer (with 10dB gain) and an AF preamplifier to boost the modulation a little. Construction is quite simple. L1 is 3.25 turns in spiral form and is an integral part of the PCB foil pattern. The two BC547 transistors can be replaced with (almost) any small-signal NPN transistor, such as the 2N2222. The final stage is a BC557 PNP general purpose device. If you use different devices then you should select the 1M0 resistor for 5-volts DC at the collector of the the first transistor. Select the 47K resistor for 3 � 4 volts on the collector of the third transistor. Here is the V5 component overlay drawing. Note that there is a modification: The PCB is 50mm x 25mm, a little larger than the first version but there are three stages instead of just the one. The first prototype is shown above, beside the battery powering it. The output power is about +10dBm which is about 10dB more than the first FM Wireless Microphone. This would theoretically give it 3.12 times the range (1.6Km) but I have only tested it using a handheld with the TX laying on the bench indoors. But I got a comfortable 700 meters (and a few funny looks from our neighbours). Above you can see the addition of a capacitor added across the 12p tuning capacitor to lower the frequency of the transmitter. Make the capacitor by twisting two lengths of single core insulated hook-up wire, about 2cm long. This will reduce the frequency to the bottom end of the band. Cut short the capacitor to increase the frequency to the desired final frequency. If you cut it a few KHz too high then just twist the gimmick a little tighter.   (View)

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Dual-Voltage Supply Powers SIM Card

Published:2012-11-8 1:07:00 Author:muriel | Keyword: Dual-Voltage, Supply , Powers SIM Card

Dual-Voltage Supply Powers SIM Card
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Cellular Telephones/Cameras

Published:2012-11-8 0:51:00 Author:muriel | Keyword: Cellular Telephones/Cameras

Cellular Telephones/Cameras
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NORELCO rechargeable electric shaver circuit

Published:2012-10-26 21: