Category Archives: Misc


Circuit Connection Tester

Here the low resistance connection tester which can be used as cable or wire tester, soldered joints and other types of connection with resistance value between 0.25 and 4 ohm. Circuit Notes: This simple circuit uses a 741 op-amp in differential mode as a continuity tester.


Diode Zener Tester Circuit Diagram

This is the circuit diagram of zener diode tester which tests zener diodes with breakdown voltages extending up to 120 volts. This is a handy circuit and will help you to measure the zener diode easily. This diode zener tester can be fitted in a 9V battery box. 1/3 of Read more…


DS1669 Digital Variable Resistor

The DS1669 is an electronic digital rheostat manufactured by Dallas Semiconductor. This component has a function similar to digital variable resistor/potensiometer which can be operated by push the buttons. You can adjust the audio volume, LCD contrast, frequency, etc. by using two buttons instead of a common potentiometer/trimpot. This circuit Read more…


Aquarium Probe Circuit Electronic

This is the electronic circuit diagram of aquarium temperature probe capable to monitor the temperature of water and indicate the rise in temperature through audio-visual indicators. This circuit uses diode 1N34 as the temperature sensing probe. The resistance of the diode will be vary depends on the temperature in its Read more…


Static Circuit Breaker Diagram

This is the circuit diagram of Static Circuit Breaker. Many a times you must have heard an undesired sharp sound emanating from the speaker, when any power appliance, like an electric iron, is switched ON of OFF. This problem is known as the Radio Frequency Interference (RFI). Some of the Read more…


Sensitive hearing aid circuit electronic

This is the circuit diagram of electronic hearing aid featured with sensitive sound detection and energy saving, so this hearing aid will work in the long term with a 9V batery battery cycle. The common hearing aid circuits consume the battery energy continuously once they are turned on. This smart Read more…


Water Level Indicator with 7 Segment LED Display

This is an unique water level indicator circuit which use 7 segment LED display to show the current water level in the water tank. Most water level indicator circuits for water tanks are based upon the number of LEDs that glow to indicate the current level of water in the Read more…


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