Posts Tagged ‘Meter’

Positive Negative Probe with IC 555

With this circuit you can can check that which dot of the circuit is Positive Volt or Negative Volt which. This cheap circuit uses the a little component is will appropriate apply with an automobile or motorcycle. This circuit works during Voltage between 5-15V. When build volt supply of circuit LED 2 pcs. of stick bright but enough check meet Positive Volt make at pin 3 of IC 555 liberate Negative volt come out cause Red LED stick bright next but Green LED switch off down replace. But when check meet Negative Volt make Red LED switch off but Green LED stick bright replace yes . The Diode 1N4002 be formed protect turning pole electricity over. The detail is other , see in the circuit please sir.

Electro meter by FET 2N3819

Today we try to come to see the circuit checks the static electricity is simple. OR Electro meter by FET 2N3819. It can show the electricity bill dwells to follow the inventory that has the electric charge. Such as the plastic is , hand , etc. By detect far get 30 centimeter. Fine the value R1 give the meter can read the value 1mA. When lead load come to near an antenna very a little ? The value will that can read to is down in proportion. Request a friend has fun Electro meter Circuit this please sir.

Simple Quartz Crystal Test with meter

In the circuit, above the BC548 is wired as a colpitts oscillator, the frequency tuned by insertion of a crystal. A good crystal will create high frequency oscillations, the output at the collector is rectified by the germanium OA91 diode and a deflection will appear on the meter. Thw more active the crystal, the higher the output deflection which may be adjusted with the preset.

Related Links
More circuit about Meter
More circuit about Crystal Test
32.768 KHz oscillator using a watch crystal

Read More Source: Andy Collinson

http://www.mitedu.freeserve.co.uk/Circuits/Testgear/crystal.htm

Thank you.