It should also be noted you can isolate the backplane/driver board ground from chassis by removing the wire from the main bus bar to heatsink ground point...sometimes a very handy feature when troubleshooting..
Exactly what Joe had me do to run the tests after each row of transistors, yes. Thanks for explaining how the grounding works, not critical for me to know but I just like things to make sense to me, a loose end thing I suppose.
You're correct, to me at least, stripping down a PL 400 and basically starting over was a little intimidating, maybe that's why it took me as long as it did to get started, in part anyway. The weather turning into REAL winter, which here in South central PA doesn't come every year, also had something to do with nudging me along I'm sure.
Daunting perhaps buy you, Joe, Doug, Nav and everyone else who drops by, looks it over and provides input has made it a hell of a lot easier than it would have been without that help, believe me! Without the assistance it may have ended up a box of parts on a shelf or at least a project that I would gladly have paid you, or one of the other guys who are willing to do them for others, to finish for me. I'm glad I get to do it this way though for the fun, education and feeling of accomplishment and am looking forward to doing my 700B
almost as much as listening to my WOPL 400. We're getting close to that, right? Thanks again my friend, hopefully I'll be able to be helpful or maybe even do a build for someone less adventurous one day. I can see it going relatively quickly once you do a few and understand it all better. This is interesting, challenging and, to top it off, fun!
I hope you're feeling better very soon my friend.