MTFCA Forum

I've a very nice period 6V battery horn (non-Ford) that I will be using on my speedster project. However, I am looking at having the car wired as close to a non-starter T as reasonably as I can. This includes the magneto horn and lights. Although an unusual set up with respect to modern conversions, but I'm wanting to operate this horn off of the magneto. My thoughts/questions are as follows:

1. I assume I will need to run it on DC. Is this as simple as putting an AC to DC converter in the circuit somewhere between the hot wire and the horn?
2. Voltage. A magneto produces several times the voltage needed to run the horn. Again, would a resistor somewhere in the system suffice? I'm aware of the effect this may have at low speeds and high speeds (weak sound and overload, respectively) depending on the size of the resistor).
3. Anything else I am missing?

The reason I want to do this is because I don't want to run a total-loss battery for accessories. I would put a magneto horn on if I come across one, but it is a very low priority item on the build budget and am not really willing to expend much energy on a search. That, and I enjoy the challenge of making a solution that works (take a battery horn, make it work on the magneto).

The Magneto produces AC voltage. After reading several old discussions and trying to piece together the answer: "yes you can" but don't do it because it will effect engine performance when you beep (ahhoooga). http://www.mtfca.com/discus/messages/70 ... 1499845931
. A Magneto horn normally draws about 2 amps AC from the magneto. A battery horn is about 5 amps when properly adjusted 6v battery. A small 6v 14AH motorcycle battery will give you more than enough beeps.

Thank you for the reply. That makes sense to me.

Look for a mag horn. There seem to be plenty @ swap meets & few people want them. I put one on my 14. Its more of an amusement, as the tone & volume radically change depending on RPM's