Date Range
Date Range
Date Range
Saturday, October 3, 2009. Low cost intercom using transistors. The circuit comprises a 3-stage resistor-capacitor coupled amplifier. When ring button S2 is pressed, the amplifier circuit formed around transistors T1 and T2 gets converted into an asymmetrical astable multivib-rator generating ring signals. These ring signals are amplified by transistor T3 to drive the speaker of earpiece. Low cost intercom using transistors.
CD-ROM drive as a audio CD player without computer. Saturday, October 3, 2009. Use the CD-ROM drive as a audio CD player without the compute. Most of the CDROMS available have an Audio-Out Output to either plug in the headphones or connect it to an amplifier. This circuit enables one to use the CDROM as a stand alone Audio CD player without the computer. This circuit is nothing but a power supply which supplies 5v, 12V and Ground to the CDROM drive and. Hence can be used without the computer.
Saturday, October 3, 2009. This circuit could be used for replacing your manual volume control in a stereo amplifier. A readily available IC from Dallas semiconductor, DS1669 is used here. Electronic interface provided for digital as well as manual control.
Saturday, October 3, 2009. Using this low-cost project one can reproduce audio from TV without disturbing others. It does not use any wire connection between TV and headphones. In place of a pair of wires, it uses invisible infrared light to transmit audio signals from TV to headphones. Without using any lens, a range of up to 6 metres is possible. Range can be extended by using lenses and reflectors with IR sensors comprising transmitters and receivers.