This ultra-simple component tester uses only 3 electronic components. With it we can check the state of resistors values less than 10k, test potentiometers, trimpots, switches, capacitors, transformers and more.
The complete taster circuit is shown in figure 1.
Its assembly based on a small terminal strip is shown in figure 2.
The box used for the assembly can be a small soap dish and we do not need switches because with separate probes, the consumption is zero.
The probes are constructed with two middle grips in which the connecting wires are soldered and then insulated with common insulation tape.
The single resistor can have values between 220 ohms and 1 k and its dissipation between 1/8 and 1/2 W.
The LED can be any color, giving preference to reds that need a lower working voltage.
To test the taster is simple. Push the test leads together. The LED should light up. If it does not light, check that the LED is in the correct position.
To test common components, the procedure is as follows:
a) Resistors up to 10k - the LED illuminates with a higher brightness, the lower the value of the resistor being tested.
b) Potentiometers up to 100k - turning the potentiometer shaft with one of the test leads in the center, the LED should change brightness.
c) Resistors over 10k - LED lights too weak or does not light
d) Capacitors - below 1 uF does not light. Above 1 uF gives a wink only the moment we lean the probes on their terminals
e) Coils- should light up
f) Transformers - should light when the same winding is tested
g) Fuses - should be on a good fuse
h) Wires - should light up if there is continuity
Never test connected devices or components that are connected to appliances.
Material list
B1 - 3 V - two small batteries
LED1 - LED red or any color
R1 - 330 ohms at 1 k - resistor
PP1, PP2 - probes - see text
Several:
Support for batteries, wires, solder, etc.
