12volts down to 6volts

[Santa Fe Bri]

Please can anyone tell how I can get my 6volt oogha horn to work on a 12volt system. :?:   Cheer`s Bri

[entodad]

Please can anyone tell how I can get my 6volt oogha horn to work on a 12volt system. :?:   Cheer`s Bri

Get a step down resister at the parts store, and run it in series with the horn...
I have absolutely no idea what Ohm rating it should have though. A sharp counter worker should be able to supply you with one...

Doug

[Pep]

Use a multimeter and test across the horn's terminal. Whatever the reading is ( and I suspect it will be fairly low about 10 ohms or so ) Then get a resistor the same and put it is series with one terminal. Make sure its at least 10 watt rating. Some heater fans use resistors around that size as well.

[1FATGMC]

Please can anyone tell how I can get my 6volt oogha horn to work on a 12volt system. :?:   Cheer`s Bri

Get a second one and run them in series.  Then you will have twice as much oogha   .

c ya, Sum

[Normspeed]

If it's a motor driven horn, it'll work pretty good as-is. It just winds up a little faster. Like a six volt starter motor on 12 volts, it turns faster and isn't likely to burn out because it's only a short burst.

[Pep]

If it's a motor driven horn, it'll work pretty good as-is. It just winds up a little faster. Like a six volt starter motor on 12 volts, it turns faster and isn't likely to burn out because it's only a short burst.

Yeah my mate did that for years.....its sounded real weird when there was a  Klaxon blowing thing happening at a run and amounst the serenade of nice sedate AhhoGahhhs came this frantic sound, 20 db louder and two octaves higher...Sounded more like ...YEEEEOOOOOOWWWW  

[Santa Fe Bri]

Thank`s Guys I get on with all that info, Cheer`s Bri

[Normspeed]

So, I guess it was a yeeooowwwwghaaa horn then...


Yeah my mate did that for years.....its sounded real weird when there was a  Klaxon blowing thing happening at a run and amounst the serenade of nice sedate AhhoGahhhs came this frantic sound, 20 db louder and two octaves higher...Sounded more like ...YEEEEOOOOOOWWWW  [/quote]

[Mr Cool]

Use a multimeter and test across the horn's terminal. Whatever the reading is ( and I suspect it will be fairly low about 10 ohms or so ) Then get a resistor the same and put it is series with one terminal. Make sure its at least 10 watt rating. Some heater fans use resistors around that size as well.

Correct Pep, however I doubt 10 watts would be anywhere near enough.
To get the correct wattage resistor, connect the multimeter in series with the horn on a 6volt supply using the Amps reading, and take a measurement.
If its using 4 Amps for example (and this is still probably conservative), use simple electrical theory as follows. Power (watts) = Volts x Amps. In this case it would be 6 x 4 = 24watts, and thats the resistor's rating you'll need to dissipate exactly half of the power through it. So make sure you get one suitably rated, to the same resistance as determined above in Peps post.
I suggest using the larger size simply due to the horns startup current is much higher than the running current, and its required to dissipate much more energy for the first 1/4 second than it normally will during use and will prematurely burn out if you dont use the right one.

[Santa Fe Bri]

Pep   I tried the horn on `12v it sounded nothing like an ooogha so I wired a 10 Watt resistor in series & didn`t get a peep out of it, if I use a 24 watt resistor what ohms value should it be........Bri

[Dave]

Pep   I tried the horn on `12v it sounded nothing like an ooogha so I wired a 10 Watt resistor in series & didn`t get a peep out of it, if I use a 24 watt resistor what ohms value should it be........Bri

Got an old ballast resistor from, a dizzy laying around? try that. that will cut it down to about 9 volts i think. It should work n/p at that.
Dave

[Santa Fe Bri]

Hey  N8Dc   Thanks for your input. I tried the 9v ign resistor, & it sounds  loads better but Im still not getting the ooogha sound., its more like a deep BIB!  it is an original 33 Ford pk up horn,, perhaps Henry Ford only fitted ooogha horns on passenger model`s ,            any feedback please................Bri

[Dave]

Hey  N8Dc   Thanks for your input. I tried the 9v ign resistor, & it sounds  loads better but Im still not getting the ooogha sound., its more like a deep BIB!  it is an original 33 Ford pk up horn,, perhaps Henry Ford only fitted ooogha horns on passenger model`s ,            any feedback please................Bri

Are sure like you said that its an oooga   horn? how bout a pic? the ooga horn should have  round but long end. look on speedways site they sell one see if it looks like that. might also try 2 ballast resistors in series that should get you closer to 6 volts to test it at least.
Dave

[Santa Fe Bri]

Hi   Dave     My Ford pk up is the same as the one on the front cover of  "Mack Hil`s" book on Ford pk up`s 1932-1952. The horn is short & has a round cap at the rear, its  mounted under the headlight bar,  I note the repro one`s different at the rear, Ive looked at the electo magnetic motor & can`t see how it would make the Ah oo Gha sound. I recon its just a BEEB any way it looks like you where right regarding using the 9v resistor Ill try 2 in series on Monday.Thanks................ Brian  

[Dave]

Hi   Dave     My Ford pk up is the same as the one on the front cover of  "Mack Hil`s" book on Ford pk up`s 1932-1952. The horn is short & has a round cap at the rear, its  mounted under the headlight bar,  I note the repro one`s different at the rear, Ive looked at the electo magnetic motor & can`t see how it would make the Ah oo Gha sound. I recon its just a BEEB any way it looks like you where right regarding using the 9v resistor Ill try 2 in series on Monday.Thanks................ Brian  

Well glad I could help. Im not very smart but I just thought the ballast resistor might get you close. I had an old big azzzzz horn off an old car but I cant remember what i did with it. I tried it at 12 volts and man was it loud
Dave