[QUOTE=01 CAt Man Do;16203737]
Originally Posted by Carib Can
This is not necessarily true. Depends on the power requirements of the actual device. If the horn requires 4A@6VDC to function to reach the proper power level and is designed to work with 6 or 12 volts you just need a voltage source capable of providing 4A@6volts. That said it stands to reason that the only thing the 12 volt switch does is provide a voltage step-down circuit that will allow the unit to function using 12 volts without burning out the other circuits within the unit that are designed to work off of 6 volts.
When you plug your Phone charger into you car cigarette plug this is in essence what is happening; The phone battery only needs so much current and so much voltage to get the job done. Basically what you get with your 12 volt phone adapter is a voltage and current regulator in one. It will charge your phone faster than your computer USB outlet only because it has been designed to supply a bit more current than what typical computer USB ports were designed for. Otherwise, the voltage/current has to step down the same way or risk frying your phone.
You are missing the whole point
As I said, current draw of a device goes up when voltage goes down, so if a device uses 2 amps at 220v that current draw will go up if it had a secondary winding for a 110v selectable circuit.
Look up Ohms law to learn a bit about current, voltage, resistance and power.
As far as phones goes, NiCads and NiMh were only limited to voltage since they took only the current they needed to be charged, they still had to have a maximum current tolerance on the charger, typically 10% of the rating of the battery.
Li Ions and Li Poly (in today's new phones) has to have both voltage and current limiting circuits since they will burn if charged with constant voltage and constant current.
I am an electronic tech by profession BTW
Don't want to go off topic here.
So, I used my Hornit yesterday and it unfortunately, it won't cut it for motorized vehicular driver attention.
It sounds like a malfunctioning car alarm on a weak car battery. I will take it back and rig something up from maybe a 6volt moped horn running two lithium ion cells rated at 1500mA and a voltage regulator.
NOTE: Cold temperatures kill Lithium Ion batteries.
The Hornit is OK for other cyclists, pedestrians and motor cyclists, it won't work for cars, vans etc.
I can actually use a decibel meter to compare before even trying it.