How to identify terminals of a mosfet.
And how to identify is it a npn or pnp?

 

MOSFETs are N or P channel.

The datasheet is the first place to check.

If not available, there will be a diode between the Source and Drain. Once you identify them, the other terminal is the Gate.

 

Most mosfets have the centre pin as the Drain (connected to the metal tab in some cases).. Best option is datasheet, or look up the fet number...

 

How to identify terminals of a mosfet.
And how to identify is it a npn or pnp?

The obvious best way is to have a part number and look to the data-sheet. Looking at a component which is unmarked in a TO-220 case less any markings there is really no way to know what you have. If it is a MOSFET and has an internal diode then as dl324 mentioned you can find the Source and Drain. Again, less a data sheet you will not know what you have or the ratings.

Ron

 

Thnx all