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Miscellaneous tools circuit diagrams
December 29, 2010
The circuit below responds to sound pressure levels from about 60 to 70 dB. The sound is picked up by an 8 ohm speaker, amplified by a transistor stage and one LM324 op-amp section. You... [more]
November 30, 2010
This is a simple servo tester which will comprehensively test the capabilities of almost any modern servo. It has two pushbuttons, CENTRE and SWEEP and a potentiometer which works as follows: - CENTRE Does exactly... [more]
November 16, 2010
A simple test circuit to fault find audio and radio equipment. Can be used to inject a square wave signal, rich in harmonics, or used with headphones as an audio tracer. [more]
November 15, 2010
This simple circuit generates narrow pulses at about 700-800Hz frequency. The pulses, containing harmonics up to the MHz region, can be injected into audio or radio-frequency stages of amplifiers, receivers and the like for testing... [more]
October 12, 2010
This circuit is not a novelty, but it proved so useful, simple and cheap that it's worth building. [more]
September 26, 2010
Short circuits or broken pcb tracks can be easily recognized by means of a Multimeter, but this tool can give wrong results when testing the efficiency of a transistor or diode, unless the device under... [more]
September 26, 2010
Although it does not have the same charm as real mercury barometers with long glass tubes on pieces of carved and polished wood, the Torricelli barometer discussed here is a functional equivalent and electronic replica... [more]
circuit from:http://www.extremecircuits.net/2010/05/electronic-torricelli-barometer.html
June 23, 2010
This Latching Continuity Tester can help you locate those difficult-to-find intermittent short and opens that other testers always seem to miss. It has been part of my workbench for many years and performs superb. I... [more]
April 23, 2010
This circuit is a frequency meter, low cost. [more]
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