Detection method of electronic tube filament open circuit
The open circuit of the electron tube filament is a relatively common fault. When the filament is disconnected, the cathode of the electron tube will not be heated, so that it cannot emit electrons, and the electron tube will not work. Because the filament of the tube is connected to the filament winding of the power transformer, as long as the filament winding of the transformer is continuous, the filament of the tube is always on when the tube is measured on the machine. The result measured at this time cannot indicate the on-off condition of the tube filament. , This will cause errors in measurement. Remove the tube from the tube socket during the inspection, find out the filament pin of the tube, and use a multimeter to check whether the filament pin is connected.
If the measured resistance is 0 ohms, it means that the filament is not broken. If the measured resistance is infinite, it means that the filament has been burned, or the filament and the pins have been disconnected, and such tubes can only be scrapped. Check that the filament of the electron tube is disconnected cannot be performed on the machine, and the tube must be unplugged from the tube socket for measurement.
Popular ic chip you may need:
NE555
YM3012
STTA1206DI
LM3886T
