555

The next section shows how the LM555 timer could be used as a voltage comparator or a wide offset Scmitt Trigger. Applications for which it is not particularly well suited but one that is in wide use with model railroaders.
Shown on the schematic is a secondary output that uses the open collector at [...]

That circuit is based at a technique to remove or neutralize the salt in water, and protect the pipes at home as well as the washing machines or our selves from salt. Its called water softener and its automated circuit using two 555 timers. The cost of parts is nearly 10$ and its very easy [...]

This circuit is a variation of the “Two Tone” siren that is a standard for the LM555 timer. The circuit allows the output frequency of the ‘B’ timer to ’sweep’ between two frequencies rather than switching abruptly between two fixed frequencies. [...]
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