View Single Post
Old 23rd Aug 2010, 12:54 pm   #11
Herald1360
Dekatron
 
Herald1360's Avatar
 
Join Date: Feb 2007
Location: Leominster, Herefordshire, UK.
Posts: 16,527
Default Re: Old car radio - how to change polarity?

Quote:
Originally Posted by Mike Phelan View Post
Ah - but the diodes in the alternator are still the same way round, so what murphy310 still stands.
I wouldn't know about that, though it seems rather unlikely that the (admittedly not exactly common but it did exist) positive earth 11AC alternator would have its diode pack the same way round as the negative earth version.

http://somerford-mini.co.uk/pdfs/Cat...lternators.pdf

has a reference to them.

Yes, "vintage" strictly means pre 1930 but my issue was about what a vintage enthusiast might have radio wise, not whether the radio came from a "vintage" car.

"ex 2 base" hasn't provided any further curiosity satiation, but I think he's been provided with suitable advice by now..... "If you can't just switch it over by design, look for a polarity inverter for the live feed to the radio"- that way the radio case can stay connected to the body of the car.
__________________
....__________
....|____||__|__\_____
.=.| _---\__|__|_---_|.
.........O..Chris....O
Herald1360 is offline