Hi guys,

and greetings from sunny South Africa.

I have an older power supply, which as soon as a load is applied, the voltage drops. I have opened it up, and found a blown cap,
as well as a blown/burnt transistor. I cannot make out the markings, so if anybody has any insight, it would be much appreciated.
I have searched the web for a circuit diagram, but no luck. Electronics is not my forte, but I'm willing to have a go! Much prefer to
repair than replace.

Thanks in advance, and pics below.





Offending parts removed: (Q3 & C3)


Component still in situ:

 

There's no voltage on there above about 25V, so almost any transistor will do, once you determine whether it is NPN or PNP. Do you have a circuit diagram?

 

Hi Ian, thank you for the reply. I unfortunately do not have a circuit diagram. The transistor is completely shorted.

 

Looks like a Philips ED1402

https://www.alldatasheet.com/datasheet-pdf/pdf/17631/PHILIPS/ED1402B.html

 

If it is a ED1402D, the discontinuation notice replaces it with a BC327.

https://www.nxp.com.cn/wcm_documents/products/eol/dn53_a.pdf

 

Thank you boostbuck! I think you may be on to a winner, certainly looks correct, and from the markings on the board, I do believe it to be a PNP. I will grab a replacement, and see what happens.