Morse Buzzer Alarm or Continuity Tester by IC 4011

This circuit uses the integrated circuit CMOS number IC 4011 pretend Square Wave Oscillator , which touch buffer change output (which compose Complementary pair of transistors) for a loudspeaker next by bass keen in the sound can control with potentiometer or 10 K ohm when we wasp the circuit suits power supply as a result , be , sound generator get , and in other words we can use to are Continuity Tester by use probe 2 reach instead of itch knock the password there. In addition Input pin , that still no use of , gate CMOS every a pin join with negative supply for feed prevent all noise.

In Circuit Transistor Checker
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 power transistors on amplifier circuits. Circuit operation is as follows. The 5 ...
Transistor quality checker with buzzer
You checked the transistor by measuring the resistance between the different pins. Sometimes it has problems, such as when measuring the resistance between the various legs correctly. But it does not work in the real circuit. Because while there is no measurement bias junction between CE. th ...
Checking Transistor with the sound
This circuit uses to check transistor get accurately and fast. By the way will check to tell with sound signal which , pertaining to the expansion ratio of transistor. Then help reduce the expenses in tool expensive buying. The transformer T1 in a picture is model output transformer at use ...
Test Transistor in Circuit by IC 4011
This circuit to Test Transistor in Circuit (PCB) Easy to use. It use IC 4011 or CD4011 or MC14011 or TC4011 , very low cost. Supply volt 9V. Related Links electronic test equipment circuit Transistor tester project Fast transistor tester circuits Frequency Doubler with 4011 Inverter ...
Fast transistor tester circuits
This circuit design, to determine quickly the transistors only. when not have time,or need to check the a lot equipment. This circuit have a simple way to work,In the test battery position (turn off switch S2).Moving coil meter 10 mA, in series with a resistance of 600 ohms(R4+R5) .When con ...