Page 121 - Testing Electronic Components

first digit is the number of junctions. However, Japanese transistors have
different type numbers. The following designations are generally used.

Japanese transistors European Type Typical example
number Type
2SA A PNP, High 2SA733=A733
frequency
2SB B PNP, Low 2SB861=B861
frequency
2SC C NPN, High 2SC5048=C5048
frequency

2SD D NPN, Low 2SD2125=D2125
frequency
2SJ J P-Channel FET 2SJ306=J306
2SK K N-Channel FET 2SK792=K792

Note that S is used to indicate a semiconductor. If you found a transistor
with the part number of C945, you will immediately know that it is a
NPN transistor.

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