I think they could need reversed. Ive had similar issues with these when I was building the Smooth / Stepped Generator, in that I think the part number I had was PN4250A which had a different pinout to the PN4250 layout on the board. Also, from the documentation of the Serge noise source module:
"Note that the orientation for the
transistors on the overlay is for vintage 2N4250 and 2N3565. The pinout
of modern PNXXXX devices is usually the reverse of what was used with
the 2NXXXX devices. In this case, BC557B and BC547 variant can be used
as direct replacements for the vintage transistors, or PNXXXX devices
can be used, but installed in reverse with respect to the transistor
outlines shown on the PCB. Whatever your choice, the tiny transistor
schematic symbol within the "D" is correct and can be followed. “
So it might be that you’ve used this before and it worked out OK because you were building it for a board marked with the PN4250 pinout rather than the 2N4250?
Cheers,
Scott.
Mon Apr 27, 2015 9:49 pm (PDT) . Posted by: spunraddishHey guys, my first post here. I wired up my wave multipliers, and almost burned myself on the 4250s - there was no smoke, and I was able to turn it off before anything got destroyed, or so I think, since when I would power it on again, the same thing would happen. I think I've used these 4250s before with other cgs boards, but didn't have to flip them around.
The top and middle section of the wave mults output nothing audible, though there may be a dc offset on the outputs, and the bottom section sounds beautiful.
I don't know much about the 3080s, they aren't a pressing matter with such heat coming off the transistors.
Any ideas?
Thanks,
Eric