Review of the DY294 Digital Transistor Tester-Part 3
Here is the part 3 of the review of the DY294 Digital Transistor Tester:
Testing FET breakdown voltage:
Every transistor have a breakdown voltage and this meter can be used to test on the N-channel and the P-channel Mosfet transistor. The test result were higher than the original value printed on the transistor spec. Please refer to the photos below for more information:
Testing SCR and Triac:
I found that the test result for SCR and Triac breakdown voltage were way out as compare to the device’s spec. This happen most probably because there is no gate signal present at the gate pin.
Testing Transistor Dc Current Gain hfe:
Sometimes a transistor can be tested okay with a normal meter but because of there is changes in the hfe value of the transistor, that particular transistor may not work when under full load. So it is equally important to test the hfe value as compare to just finding out the base, collector and emitter pin of the transistor. Below are the photos of the test result;
For your information, if the Horizontal Output Transistor (HOT) have a built in damper diode then this tester can’t test out the hfe value. It will just show “0.00” result.
What About Testing Other Transistor Parameter?
Well , the test result are more or less the same as testing the FET breakdown voltage. Just do not expect it to be exactly the same with the transistor specification downloaded from the internet.
Comment about this meter?
The disadvantage of this meter is that it does not have a proper probes to hold the components and you have to insert the components into the desire socket and this can cause the internal socket to loosen easily. Second, external 6 volt 2 amp dc power supply may be needed to test on high power transistor. Third, the manual provided especially the connection of the components was quite blur. Since this meter is quite cheap and have the ability to test so many components, you have nothing to loose to own one.