The positive and negative electrodes of the test self flashing light emitting diode can be used as a universal table R * 1K file or R * 10K file (in case of MF47 type universal meter). When using the RXlkQ file, with the red and black two pens are respectively connected with the two lead flash light emitting diode, and then the red and black pen on the re test since flash two leads light emitting diode, a resistor (big hands slightly swinging, black) is a flash luminescence probe connected to two pole tube the red pen is connected with the cathode, anode from flash light emitting diode, as shown below. If you use R * 10K ohm measurement method according to the above, when a hand swing amplitude resistance of 1cm, and the tube will be flashing light in the core. This phenomenon indicates that the power supply from the flash light emitting diode is connected with the correct polarity (i.e. the black probe connected is positive flash light emitting diode), circuit oscillation.


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