Hello is there a good web site for identifying surface mount transistors
i did find an old site www.sos.sk/pdf/sm_catalog.pdf
i attached photo of this transistor small t 23
measures like PNP with resister on base
Hmm. SMD Cookbook (https://www.sos.sk/pdf/SMD_Catalog.pdf) thinks it's PDTA114TU.
This one thinks there's a few similar candidates - http://www.smdmark.com/en-US/smd-code-T23.html
It's usually quite tricky to know for 100% certainty given how little information can be etched onto the surface of such a small component.
I normally use S-manuals - it doesn't even have it listed. https://www.s-manuals.com/smd
Trouble is there is no complete consensus on these markings and there are duplications so you need to consider the style of the markings and double-check with the spec. sheet of the manufacturer (usually the last sheet before the performance graphs).
If you can use an Atlas semiconductor tester (fun with smt!) it will identify the nature of the component IF it is still what it should be - blown FETs test as a diode junction normally.
Then head to the web until you get consistent answers - the silk-screen legend can help after all a D102 is not likely to be a transistor (you hope) but a Q102 or TR102 will!
Certainly looks to be a PDTA123JT as anniel747 suggests.
once i have a known part then i use
that saves time
this transistor is out of Zeck Gross-funk remote control cable winch
that is used on the high voltage pylons
and i have since found 2 more dead transistors that this one supplies
i don't know what caused this to fail
of course all the manufactures would do is sell you another box $000 + fright