PA0O ham radio

                on eBay or UTsource (above)   its all fake UT source did refund  left is the genuine a bit smaller then the TO220 IRF stamped as RD15HVF1 The original RD15xx types have a small Gate to source C ca 80pF and the source at pin 2 The fake have high gate - C  this one 800-900pF  and its source is pin 3 like all IRF -types The IRF510 has the lowest gate capacity of about 400pF the best of the rest Misubishi's   RD15HVF1 is an  UNIQUE  VHF power FET. With its Source at pin2 = cooling flange,  the only right  place of course No other manufacturers deliver comparable divices. It must be hard to produce. The eBay offered types are all fake cheap IRF5xx imitations in fact fraude. The RD15xxx is relative expensive for a small FET  5-7€  from vendors that will easy take 50$ or more for shipment. Not sold by  Farnell Digi Key Reicheld  and Mouser In RF high...