Automatic cooler fan for amplifiers

jacky April 7, 2010 27 Comments
Description. The schematic of an automatic cooler fan for audio amplifiers is given here. The circuit automatically switch ON the cooler fan whenever the temperature of the heat sink exceeds a preset level. This circuit will save a lot...
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Police siren using NE555

jacky January 27, 2014 16 Comments
Description. A lot of electronic circuits using NE555 timer IC are already published here and this is just another one.Here is the circuit diagram of a police siren based on NE55 timer IC. The circuit uses two NE555 timers...
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Hall Effect switch

jacky February 26, 2010 8 Comments
Description. The circuit diagram shown here is of a Hall Effect switch. Hall Effect sensor IC DN6848 from Panasonic is the heart of the circuit. The DN6848 has a built-in Hall Effect sensor, Schmitt trigger circuit, power supply regulator...
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Speaker protector

jacky April 7, 2010 6 Comments
Description. When the amplifier is switched on, the speaker gets popped up by a high voltage and you can hear a loud thud sound from the speaker. This stuff is very harmful to the speaker and it drastically reduces...
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Audio line driver

jacky April 7, 2010 56 Comments
Description. This is the circuit diagram of a two channel audio line driver using the high performance dual opamp IC TSH22 from ST Microelectronics. The 25 MHz bandwidth, low distortion and high output current of the IC makes it...
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One transistor code lock

jacky March 3, 2010 19 Comments
Description. This is of course the simplest electronic code lock circuit one can make. The circuit uses one transistor, a relay and few passive components. The simplicity does not have any influence on the performance and this circuit works...
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Hi-Fi DX Bass circuit

jacky April 7, 2010 47 Comments
Description. Here is the circuit diagram of a passive DX bass circuit that can be used with almost all audio amplifiers. This circuit is designed by Mr. Emmanuel Chipula ( from Malawi and was sent to us for publication.We...
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24V lead acid battery charger circuit

jacky March 12, 2010 149 Comments
Description. This lead acid battery charger circuit is designed in response to a request from Mr.Devdas .C. His requirement was a circuit to charge two 12V/7AH lead acid batteries in series.Anyway he did not mentioned the no of cells...
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Car subwoofer filter

jacky April 7, 2010 30 Comments
Description. Here is the circuit diagram of a simple subwoofer filter that can be operated from a 12V DC supply. Such a circuit is very useful in automobile subwoofer applications. The circuit is nothing but a low pass filter...
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