Silicon, high-voltage, mesa-planar powerful transistor kt838 npn structures were used mainly for horizontal scanning of TVs and also in switching power supplies. and released. Let’s look at the main characteristics of this transistor.
- Collector-emitter pulse voltage 1500V
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DC collector current 5A pulse current 7.5A (кт838а,б)
- Cutoff frequency 3MHz
- Collector-base pulse voltage 1500V(кт838а) кт838б -1200V
- h21э-4
- Power dissipation-12.5W
Please note that this is a switching transistor and the voltages are indicated in switching mode. The body of the transistor is the collector terminal.
When checking the transistor with a tester, it can be seen that the gain of the transistor is small, only 3. In this transistor, unlike more modern foreign analogues, there is no low-resistance resistor between the base and emitter, and there is also no damper diode between the collector and emitter. This resistor and the diode was connected separately on the board, this can be seen from the line scan scheme from the TV.
