I was recently given a Spectrum 300 plasma that's not operational. Looks like two of the main power transistors have popped, unfortunetly bad enough that I can't read any kind of part number on them to source replacements.

Is there any way to get these numbers, short of buying a replacement board? I've attached pictures of the affected units, and in the wide shot, it would be the 2nd and 4th heat sink from the left.

I can handle the replacement no problem, I'm quite familiar with working with electronic components, and have the full service area here at the house for electronic work - temp controlled solder stations, hot air station, static controlled work area, etc. Just need to know what transistors are in there, lol.

Also, any idea what would have caused this?

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