The triode can be judged as being good or bad in the following way:
1. Base and tube type discrimination method:
Measured germanium tube with R × 100 file, silicon tube with R × 1K file, first fixed red pen and any one foot contact, black pen were measured on the remaining two feet. See if you can measure to two smaller resistance value, if not then move the red pen to the other foot to continue to measure the two small resistors, if the fixed red pen can not find two small resistors, you can fix the black pen to continue to find. When you find two small resistors, a fixed pen used for the base of the foot.
If the fixed pen for the black pen, the transistor for the NPN type, if the fixed for the red pen, the tube is PNP.
2. Identify the collector:
Because the transistor emitter and collector correctly connected β is large (the needle swing is large), reverse connection β is much smaller. Therefore, the first assumption of a collector, with ohm gear connection, (for PNP-type tube, the emitter connected to the black pen, collector connected to the red pen). Measurement, hand pinch (or connect with a 100KΩ resistor) the base and the assumed collector, the two poles can not be contacted, if the pointer swing is large, while the two poles are adjusted to the pointer after the pointer swing is small, it means that the assumption is the correct collector, so as to determine the collector and the emitter.
According to the resistance value of the triode you described above is either the multimeter is faulty, or the triode is bad. Or first find a good triode according to the above method of measurement and then compare, you can determine the good and bad as well as lessons learned.
Triode pin must be correctly identified, otherwise, access to the circuit not only can not work properly, but also may burn the transistor.
