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Tools and measuring circuit diagrams
November 25, 2010
This circuit enables you to test quartz resonators at the range values from 32kHz to 24MHz. Confirmation of good state of quartz resonator is done by diode signalling LED and acoustic signal [more]
November 16, 2010
This low voltage circuit can be used to monitor batteries and other volatile sources of current for problems. The circuit sounds an alarm and lights an LED, but can be interfaced to any number of... [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
A low resistance ( 0.25 - 4 ohm) continuity tester for checking soldered joints and connections. [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 18, 2010
This is a variation on the astable multivibrator. Circuit was recently developed to test for N-mosfets(the power kind e.g irf830) [more]
October 12, 2010
This simple circuit has helped me out on many occasions. It is able to check transistors, in the circuit, down to 40 ohms across the collector-base or base-emitter junctions. It can also check the output... [more]
October 12, 2010
This circuit is not a novelty, but it proved so useful, simple and cheap that it's worth building. [more]
October 5, 2010
This is a simple XTal tester circuit. T1 and XTal have formed an oscillator. C1 and C2 are voltage divider for oscillator. if the XTal is safe, the oscillator will work well and its output... [more]
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