Why positive ground?

[Henry's Lady's Man]

FWIW, From what I've read, the wiring back then was cloth. When cloth insulation got wet, it would "bleed" electricity to the body where it made contact. With negative ground, this left corrosion at those spots. With positive ground, it did not leave corrosion. So, in the late 50's, WIRING INSULATION WENT TO THE NEW PLASTICS, AND MADE THE CORROSION A NON-ISSUE... no more "bleed".
The other development was that AT THE SAME TIME, car radios started using diodes which passed electricity only one way, necessitating negative ground (Oh, maybe the electronic engineers could have made diodes pass the OTHER way, but they didn't?).
SO AT THIS POINT, NEGATIVE GROUND worked for radios, and there was no more corrosion issue ('cept at the battery terminal).
Somebody will correct me if I am wrong. Chuck

 

[Mike V. Florida]

The question of why Henry Ford used positive ground for so many years comes up occasionally on Fordbarn.

Toe may to
To mot to

 

[modelaer]

FWIW, From what I've read, the wiring back then was cloth. When cloth insulation got wet, it would "bleed" electricity to the body where it made contact. With negative ground, this left corrosion at those spots. With positive ground, it did not leave corrosion. So, in the late 50's, WIRING INSULATION WENT TO THE NEW PLASTICS, AND MADE THE CORROSION A NON-ISSUE... no more "bleed".
The other development was that AT THE SAME TIME, car radios started using diodes which passed electricity only one way, necessitating negative ground (Oh, maybe the electronic engineers could have made diodes pass the OTHER way, but they didn't?).
SO AT THIS POINT, NEGATIVE GROUND worked for radios, and there was no more corrosion issue ('cept at the battery terminal).
Somebody will correct me if I am wrong. Chuck

Radio at the time did not require polarity to be an issue. Radio vibrators would work for either pos. or neg. ground and as long as the voltage of the tube plate is more positive than the cathode all is well. Solid state radio is a different story. Solid state came in in the 1960's long after the change over to negative ground. Alternator diode bridges during their development were possibility the reason for standardizing the ground polarity.

Pete