Summary

The Steel needle goes on the bed.
The Servo lift the needle thrue the optical Endswich if retracked -> switch triggered.
Requires a small SW fix in Marlin. (Delay after deploy the probe)

If it is deployed the servo provides pressure on the Spring to hold the needle down during probing.
-Givs more acurate and servo independ Probe mesure.
-Probes also Glas or blue Tape.
-Probe mechanic could be over the Print Head,

Ususal due to the glitches in the servo control pwm and the servo itself the standard Servo Probe is not that acurate.