Our son was once into restoring cars and today I found this "left over" horn from his collection of spare parts.
Used in Ducati, VW, Mercedes amongst other German manufacturers, I believe he was going to use this with a Merc W116 but not positive about that.
BOSCH - Automotive Horn
Made in Germany
Part numbers - identification stamped into the rear
DGM10146KA
CH5 03010
BOSCH
Made in Germany
e1 20002
A 71222
4.5" diameter (114mm)
12V DC operation
2x screw terminals
Mounting bar is included
COSMETIC CONDITION:
USED
CLEAN
NO damage to the horn body
I do notice that one terminal screw is missing, I would assume these are common in an enthusiasts workshop
TESTING:
Not much good offering a horn if it doesn't work!
I first made a DC resistance test across the terminals and was surprised to read an open circuit, I was expecting to be looking at a coil of some type so this means there must be some electronics inside these horns.
Immediately upon applying power (12V DC) the horn fired up and SPOKE LOUDLY!
These horns suck a fair bit of current, if I tested at a current limit of 2A it would only faintly buzz away but once I allowed up to 5A current to flow, it fired into full action.
I don't know the loudness rating but this horn is louder than the Knight Horns I also had recently and they were rated at 105dB
I used to have a portable sound level meter but, like so much of my test equipment, it went off to a new home so I couldn't measure the loudness. Suffice to say, this horn bought the neighbours to attention!
I have now packed this horn into a sealed, clear plastic packet and it now patiently waits to live near another engine bay.
