The W201 (190E) uses a hall effect but the pictures that are posted are on an INDUCTIVE style pick-up.
Hall effect is an on/off signal needing a voltage supply while the inductive(pictured) supplies A/C voltage.

__________________
MERCEDES Benz Master Guild Technician (6 TIMES)
ASE Master Technician
Mercedes Benz Star Technician (2 times)
44 years foreign automotive repair
27 Years M.B. Shop foreman (dealer)
MB technical information Specialist (15 years)
190E 2.3 16V ITS SCCA race car (sold)
1986 190E 2.3 16V 2.5 (sold)
Retired Moderator