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Old 12-14-2020, 09:04 AM   #1
TJMack
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Default AAOOGAH horn regulator

I only know enough electronics to be dangerous so I'm wondering if we have any electrical technicians who might be able to help with something I've been wondering about.


My horn works perfectly with the engine off or at idle giving off the desired 3 step response; AHH OOOG AHH. But at road speed with the amperage (and voltage) up it runs too fast and only goes OOG AHH.


I'm wondering if a diode or something could be added to the horn wire that would limit the voltage to 6 volts. I've heard of a Zenner diode and an avalanche diode, but don't know enough about that stuff to figure out what might work
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Old 12-14-2020, 09:45 AM   #2
Badpuppy
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Default Re: AAOOGAH horn regulator

I think this is fairly normal behavior. You can try adjusting third brush voltage downward if you drive mostly at speed. Otherwise you need voltage regulation from the generator. A zener wouldn't handle the current required.
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Old 12-14-2020, 09:46 AM   #3
Mister Moose
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Default Re: AAOOGAH horn regulator

A diode's main job is to operate as a one-way street. Current only flows in one direction through the diode.

What you want to do is regulate voltage. Are you on a generator? It's going to be more complicated to do if you are.
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Old 12-14-2020, 11:12 AM   #4
nkaminar
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Default Re: AAOOGAH horn regulator

Try adjusting it first. If that does not work you can add a resistor to drop the voltage. A diode will have a voltage drop too. The trick is to get a diode or resistor that will take the current. The voltage drop plus current equals heat.

The parts suppliers sell resistors that are meant to drop 12 volts to 6 volts that may work with your 6 volt system. Some are designed to be mounted to the frame and will take continued use of the horn while others mount inside the horn and are for intermittent use. Both are mostly plug and play so you should have no problems installing them. I have the latter and it works fine as I don't lay on the horn for more than a few seconds.

I don't know what the current is but I would guess at around 6 amps.
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Old 12-14-2020, 11:17 AM   #5
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Default Re: AAOOGAH horn regulator

You can also build or possibly buy a voltage regulator. Do a google search for a voltage regulator or voltage regulator circuit.
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A is for apple, green as the sky.
Step on the gas, for tomorrow I die.
Forget the brakes, they really don't work.
The clutch always sticks, and starts with a jerk.
My car grows red hair, and flies through the air.
Driving's a blast, a blast from the past.
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Old 12-14-2020, 11:32 AM   #6
Will N
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Default Re: AAOOGAH horn regulator

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When do you generally use your horn? If its for show purposes only and you show the ahoodah off while it's parked, leave things be. If you use it while driving to warn others, adjust your horn, turning the screw in a couple clicks, to get the desired ahoogah while the engine is spooled up.
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Old 12-14-2020, 11:36 AM   #7
jrelliott
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Default Re: AAOOGAH horn regulator

First, are you running 6V or 12V? Adjusting the horn would be the first step if running a stock 6V system. The dropping resistor could be added if running a 12V system.
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Old 12-15-2020, 08:46 AM   #8
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Default Re: AAOOGAH horn regulator

Quote:
Originally Posted by nkaminar View Post
You can also build or possibly buy a voltage regulator. Do a google search for a voltage regulator or voltage regulator circuit.
VRs on Amazon or Ebay generally are designed for negative ground systems. You might find one to work with pos ground, but you would have to see the schematic to know.

And yes, the horn requires about 6A.
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Old 12-15-2020, 03:15 PM   #9
J Franklin
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Default Re: AAOOGAH horn regulator

Add 1 or 2 clicks to the adjusting screw and go for a ride.
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