Decwriter power supply transistors R3004 - test-drb@ccmp.vtda.org

17 Jun 2013

...
  The printset identifies them as "NPN 100W S1325
15". 
Aha - SI = Silicon, and so on. I vaguely remember that thread now.

...
  So I guess you're looking for a silicon NPN
transistor with 100W
 max power dissipation, a Vceo of 325V or better, and an hFE about
 15 (and the right pinout!). Tony or one of the other PSU gurus can
 probably suggest something that'll do the job?  
Likely candidates might be (from parametric search on newark.com): 
BUX80, BUY69A, 2N6308, 2N6547, then.

Anyone know of any contraindications for any of these?

I'll see what Al Lasher's Electronics in Berkeley has on hand before I 
shop the interwebs.