Horn wiring

[3Dueces]

This is off a 1936 car. I believe it is a Sparten horn. I want to wire it up but have no idea as to what pole is what as far as polarity is involved. It is a positive ground car. It will honk off a spare battery either way, but it would be nice to solder the leads correctly the first time. Any ideas? Thanks...

 

[koates]

There should be a twin brass connector terminal inside the horn where the two harness wires push into. That terminal appears to be missing on your horn. The horn does not care about the polarity and will work OK either way. Early Fords were positive to ground/chassis . Regards, Kevin.

 

[rotorwrench]

Kevin has it. A ******** circuit isn't affected by polarity changes. Here is a link that shows a photo. https://www.fordbarn.com/forum/showthread.php?p=661057

12-volts might be a bit much for an old horn for those that change. Most folks that change polarity also change voltage. On a 6-volt system like the OP has, I just leave them positive earth/ground. ******** circuits and series wound motors can work normally with polarity changes. Radio sets with the old ******** coils can also work either way. Modern solid state ******** replacements are polarity sensitive.