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December 8, 2010
A switched timer with equal make and equal space periods timing adjustable from over 6 minutes to 38 minutes. [more]
December 8, 2010
This circuit is intended for children fun, and is suitable to be installed on bicycles, battery powered cars and motorcycles, but also in models and other games. [more]
December 8, 2010
This circuit uses a CA3420 BiMOS op amp to form a picoammeter with 4 ranges. The exceptionally low input current (typically 0.2pA) makes the CA3420 highly suited for use in a picoammeter circuit. Input transient... [more]
December 3, 2010
This circuit generates a two-tone effect very much alike the cuckoo sound. It can be used for door-bells or other purposes thanks to a built-in audio amplifier and loudspeaker. [more]
December 3, 2010
This simple circuit mixes two or more channels into one channel (eg. stereo into mono). The circuit can mix as many or as few channels as you like and consumes very little power. [more]
December 3, 2010
Built around a single 8038 waveform generator IC, this circuit produces sine, square or triangle waves from 20Hz to 200kHz in four switched ranges. [more]
December 3, 2010
This simple counter can be used to count pulses, as the basis for a customer counter (like you see at the doors of some stores), or for anything else that may be counted. [more]
December 3, 2010
This circuit is a 73 MHz Hallogene Lamp Radio-Controlled. The purpose of it is to control the power state of a hallogene lamp by a remote control. [more]
December 2, 2010
This is the schematic for an FM transmitter with 3 to 3.5 W output power that can be used between 90 and 110 MHz. Although the stability isn't so bad, a PLL can be used... [more]
December 2, 2010
A truly timeless circuit. LM317 is a versatile and highly efficient 1.2-37V voltage regulator that can provide up to 1.5A of current with a large heat sink. It's ideal for just about any application. This... [more]
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