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Recently added diagrams and projects
November 11, 2010
Here is a simple transmitter that when connected to a phone line, will transmit anything on that line (execpt the dial tone) to any FM radio. [more]
November 11, 2010
This circuit is intended to let the user turn off a lamp by means of a switch placed far from bed, allowing him enough time to lie down before the lamp really switches off. Obviously,... [more]
November 11, 2010
The basic circuit illuminates up to ten LEDs in sequence, following the rhythm of music or speech picked-up by a small microphone. The expanded version can drive up to ten strips, formed by up to... [more]
November 10, 2010
This circuit, connected with 32 Ohms impedance mini-earphones, can detect very remote sounds. Useful for theatre, cinema and lecture goers: every word will be clearly heard. [more]
November 10, 2010
This circuit is deliberately limited in power output but will provide amplitude modulation (AM) of voice over the medium wave band. [more]
November 10, 2010
This lovely circuit is a real gem! Easy to assemble and more sensitive than many commercial devices available. [more]
November 10, 2010
Feeling chirpy? Attract new friends with this modified hartley oscillator. You could also use it as a replacement doorbell. [more]
November 9, 2010
The circuit is simple, yet is capable of excellent performance. I designed it specifically for use as an amplifier for the digital sound card in my computer. Audio input can be from any two-channel line... [more]
November 9, 2010
While talking to a distant subscriber on telephone, quite often we feel frustrated when the voice of the distant subscriber is so faint that it is barely intelligible. To overcome the problem, circuit of an... [more]
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