Boots, I think Tony (Sprinkler Guy) might be referring to the old "hot common" Irritrol clox.... much like the old radios you refer to that we've both obviously worked on
I've noted, too, that most all the better clox today have a position for an "earth ground" wire...
PIA as it may be, it's a good idea... gives a great path for lightening and really "lights up" those MOV's!!!
The Irrigation Specialist Mfg' Az.
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