I want to fit my 6 volt 1928 Model A Ford Klaxon horn to the SR.

In the past I've tapped into the battery to give a separate 6 volt circuit so it sounds as it should.

If a 6 volt Klaxon horn is run on 12 volts, it goes too fast and sounds like AAAAAAAAAAGGGHHHH!!!!!!

On 6 volts it goes AAAAAAGGGGGGGGG-----GGG---GGGG---HHHHHOOOOOOGGGHHHHAAAAAA!!!

How can I drop the voltage to 6 volts at the horn and keep the same amperage?

I've thought of wiring a 6 volt wiper motor into it in series but I don't have one to try it with.

What do you suggest?

There is a bloke who offers a thingie on ebay occasionaly that cuts the voltage down to 6v, looks kinda small and he gives a description of how it works but it's all dutch to me, he offers them specificaly for klaxons, I found it by typing in" klaxon" in the search box, I'll see if I can chase down the contact. My Klaxon just will not work at all on 12v but on 6 it dosn't make the arhoogar sound, jost a long blast, I've heard that they can be adjusted, dio you know anything about this. Oh, no I don't have one of these gizmoes just always meaning to get one.

If its a genuine 28 A model Ford horn sell it there worth a bucket of money

Guess you could measure the resistance and then put a resistor (of suitable power rating) in series with the horn

My Klaxon has an adjustment screw in a small hole in the motor cover.

I'd suggest that you remove the cover of yours and see if there is an adjustment screw inside.

How about fitting two ballast resisters in series as this worked well for me when providing 12 volt power to a 6 volt wiper motor so they ran at normal 6 volt speed

Well tracked it down best I could. Sellers name is rbruce84 but dosn't seem to be trading at the moment. he pops up occasionaly as I've seen his item come up now and then, he is a klaxon restorer.