Final Procedure

TB 9-4920-451-35

b. Adjustments

(1) Set MEGOHMMETER OFFSET trimmer screw (fig. 1) for meter indication that is

the same value as stamped above S8 switch (fig.1) (R).

(2) Set MEGOHMMETER GAIN (fig. 1) until meter agrees with value stamped above

switch S9 (fig.1) (R).

12. Final Procedure

a. Deenergize and disconnect all equipment.

b. Annotate and affix DA label/form in accordance with TB 750-25.

SECTION IV

CALIBRATION PROCESS FOR

GULL AIRBORNE INSTRUMENTS, MODEL GTF-4

13. Preliminary Instructions

a. The instructions outlined in paragraphs 13 and 14 are preparatory to the calibration

process. Personnel should become familiar with the entire bulletin before beginning the

calibration.

b. Items of equipment used in this procedure are referenced within the text by common

name as listed in table 2.

c. Unless otherwise specified, verify the result of each test and, whenever the test

requirement is not met, take corrective action before continuing with the calibration.

Adjustments required to calibrate the TI are included in this procedure. Additional

maintenance information is contained in the manufacturers' manuals for this TI.

d. Unless otherwise specified, all controls and control settings refer to the TI.

14. Equipment Setup

WARNING

HIGH VOLTAGE is used or exposed during the performance of

this calibration. DEATH ON CONTACT may result if

personnel fail to observe safety precautions. REDUCE

OUTPUT(S) to precautions. REDUCE OUTPUT(S) to

minimum after each step within the performance check where

applicable.

a. Remove top protective cover as required for adjustments.

b. Connect TI to 115 V, 400 Hz, using cables supplied with TI.

c. Set POWER ON/OFF switch to ON and allow at least 30 minutes for warm-up and

stabilization.