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Sensor circuit diagrams
November 30, 2010
The 555 is proved to be the most versatile and ubiquitous IC all over the world.This is a possible use: simple inverting schmitt trigger. [more]
November 26, 2010
This sensitive sound operated switch can be used with a dynamic microphone insert as above, or be used with an electret (ECM) microphone. If an ECM is used then R1 (shown dotted) will need to... [more]
November 25, 2010
The purpose of this circuit is to animate shop-windows by means of a capacitive sensor placed behind a post-card-like banner. [more]
November 18, 2010
This circuit is intended to signal when a plant is needing water. A LED illuminates at maximum brightness when the ground in the flower-pot is too dry: it dims gradually as the water's content in... [more]
November 15, 2010
This circuit is intended to signal through a flashing LED, the exceeding of a fixed threshold in room noise, chosen from three fixed levels, namely 50, 70 & 85 dB. Two Op-amps provide the necessary... [more]
November 15, 2010
This circuit was designed to detect the approximate percentage of salt contained in a liquid. After careful setting it can be useful to persons needing a quick, rough indication of the salt content in liquid... [more]
November 15, 2010
This circuit uses a sensor made of a small piece of etched PC board and a simple SCR circuit to detect rain and sound a buzzer. The SCR could also be used to activate a... [more]
November 10, 2010
This lovely circuit is a real gem! Easy to assemble and more sensitive than many commercial devices available. [more]
November 8, 2010
Here's a simple lie detector that can be built in a few minutes, but can be incredibly useful when you want to know if someone is really telling you the truth. It is not as... [more]
November 8, 2010
Imagine that is morning , you barely anticipate the bus for work and you can't find your keys. If you suffer from this situation frequently, this circuit is ideal for you. A fizzle is the... [more]
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