From the FB group Building Transistor Radios
Willie Barnett
The generic 901x series are very cheap jellybean transistors used in consumer electronics, typically made in Asia. The 901x was preceded by C, but other companies used other prefixes such a S901x for Fairchild (now ON Semi), or CC901x, or even MPS901x or MMBT for surface mount. I believe Korean Semi called it KSC901x. Some have ID’d it as 2SC901x, but I have never seen a datasheet with that. You can find the datasheets for the series online. There are also two other transistors typically used as high current switches in motorized toys, etc. The 8050 in NPN and the 8550 is PNP. The above also applies to these two. All of these transistors come in the standard TO-92 package with the E B C pinout.