[Johnson] Valiant II Problems

[BRIAN ROBERTS]

Hello Gents:
I've picked up a basket case Valiant II, and am trying to get it back into operating condition.  It's a tedious process as there are a number of undocumented mods to the transmitter, and the previous owner is now a silent key.  Smoke tests have successfully produced smoke on a couple of occasions, but I'm puzzled as to why there would be arcing noises coming from within R-51 (grid drive control) along with some smoke.  The driver screen bypass and tube are not shorted.  Thanks.  Brian K9VKY