darn, broke it!

Well, I started implementing the changes I've identified as needed.  And unfortunately, I broke something.  I removed the boost switch from the signal path, putting the third triode stage into the path following the mixer resistors for both preamps -- or so I thought.  But instead of getting louder, actually everything got quieter.  The VTX preamp was very quiet even at max volume, and interestingly, the AB763 was even quieter, barely audible at all.  So at least I managed to more than equalize the levels of the two.  But clearly, something is wired wrong.
Taking a break from it as I regroup.  Tomorrow, I'll try to debug this.  I'm glad I've heard it get loud before these changes, or I might worry that my cathode-biased power amp design was faulty.

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