36 Electrical standard equipment

Signal horns

The model series P1800 is equipped with two signal horns, a low tone horn and a high tone horn.

Up to model year 1964 (D; ch -12.499, excl. 12.441), vehicles of the P1800 and 1800S series also have a supertone horn for interurban and motorway driving. It is operated with a long lever arm (#664478) on the right side of the steering column.

switch 664478

horns 12499

The horn can only be operated when the ignition is switched on. Switched plus (ignition plus) is then present at terminal W1 of the relay.

 The operation of the two signal horns and the supertone horn is shown in this video (© Robert Schlecht).


From model year 1965 (S,ch 12.500-, incl. 12.441) the supertone horn is no longer fitted. The lever arm is replaced by the lever arm (#664473), with which the overdrive is switched on.

Übrigens, Mercedes-Benz spendierte seinen Fahrzeugen nur Starkton-Hörner, denn auch in der Innenstadt sollte man sich bemerkbar machen können.

Construction

The horns are so-called impact horns, an electromagnet with a breaker sets a membrane in vibration. This produces a fundamental tone. Permanently connected to the diaphragm is a vibrating plate or vibrating bar, which produces overtones by the impact of the armature on the magnetic core.

schema horn

  1. Cover
  2. Screw
  3. Housing
  4. Capacitor
  5. Contact breaker
  6. Adjusting screw for contact breaker
  7. Attachment
  8. Leaf spring
  9. Iron core
  10. Winding
  11. Armature plate
  12. Diaphragm
  13. Vibration disc
  14. Adjusting screw
  15. Lock nut

 

BOSCH HO/FDG 12

FDG = horn version for passengers cars
Diameter: 125 mm
Cover and housing: black
12 = version for 12 V

Low tone BOSCH HO/FDG 12 (10/9)
VOLVO #238686
10 = xx
9 = xx
Frequency: 290 Hz
Volume:110 db (A)

Tweeter BOSCH HO/FDG 12 (11/9)
VOLVO #238685
11 = xx
9 = xx
Frequency: 362 Hz
Volume: 110 db (A)

The difference between the two signal horns is the oscillating diaphragm (pos. 31)

bosch ho fdg 12

BOSCH HO/FSA 12/27 Supertone horn

VOLVO #238714

FSA = Version as supertone horn, especially suitable as overtaking signal
12 = Version for 12 V
27 = xx
Diameter: 155 mm
Cover and housing: black

Frequency: 520 Hz
Loudness: 118 db(A)

bosch ho fsa 12 27

bosch ho fsa 12 27 01

Picture © J Graham Coutts (CAN)

1800E 1800ES


Low pitch VOLVO 680860 325 Hz
High pitch VOLVO 680859 400 Hz