Transistor S9015 p-n-p conductivity,low-power,low-noise,silicon,high-frequency.It is available in the TO-92 housing and for surface mounting (for smd, the power characteristics are less).Such a transistor used to be often found on consumer electronics boards, today it is used less often, in the photo there are four transistors on the aerogrill control board.The complementary pair is the transistor S9014.
The main characteristics of the transistor:
Collector-emitter voltage 45 Volts Collector-base voltage 50 Volts Emitter-base voltage 5 Volts Collector current 100 mA Dissipated power 450 MW noise level from 0.7 to 10 dB gain with letter A 60-150; with letter B 100-300; with letter C 200-600; with letter D 40-1000 limit frequency up to 190 MHz operating temperature range from -55 to +150 degrees
The transistor tester will show the characteristics and pinout of the transistor.
On this transistor, you can assemble simple circuits of chargers for a 3.7 Volt battery.