Make the following initial settings on the Eddy Current Inspection Unit, NORTEC-1 9ell.
Refer to Eddy Current Method, paragraph 1.4.11. Set up on test block as follows:
(1) Null probe on test block.
(2) Adjust phase as required to obtain horizontal lift-off.
(3) Move probe over all three notches in test block. Adjust gain to obtain a three block vertical signal when probe is
passed over 0.040-inch notch in test block. (See the standard instrument display shown in Figure 1-7.)
18.104.22.168 Inspection Procedure. Refer to Eddy Current Method, paragraph 1.4.11 and Figure 2-11.
Figure 2-11. Main Rotor Head (Hub)