TB 9-6625-2076-35
14. Radial Accuracy
a. Performance Check
(1) Connect ZIFOR III input to TI COMP output (rear panel).
(2) Press TONE SELECT 30 Hz VAR and 9960 FM pushbuttons (all other TONE
SELECT pushbuttons off).
(3) Press FUNCTION/CONTROL RDL/DDM pushbutton and enter 000.00 into TI
for a FROM 000.00 RDL/DDWMOD indication. ZIFOR III indications will be between
359.86 to 0.14 degrees radial.
(4) Enter RDL (DEG) settings listed in table 8 into TI. ZIFOR III indications will
be within limits specified.
NOTE
Proper 30 degree radial steps can be entered by pressing
FUNCTION/ CONTROL STEP ∆RDL ∆DDM pushbuttons.
Test instrument RDL
ZIFOR III indications (DEG)
(DEG)
Min
Max
030.00
029.86
030.14
060.00
059.86
060.14
090.00
089.86
090.14
120.00
119.86
120.14
150.00
149.86
150.14
180.00
179.86
180.14
210.00
209.86
210.14
240.00
239.86
240.14
270.00
269.86
270.14
300.00
299.86
300.14
330.00
329.86
330.14
b. Adjustments. No adjustments can be made.
15. Localizer DDM
a. Performance Check
(1) Connect digital multimeter to TI COMP output (rear panel).
(2) Press FUNCTION/CONTROL STD pushbutton and enter a frequency of
108.10 MHz into TI.
(3) Press TONE SELECT 90 Hz pushbutton (all other TONE SELECT
pushbuttons off). Record digital multimeter indication
(4) Press TONE SELECT 150 Hz pushbutton (all other TONE SELECT
pushbuttons off). Record digital multimeter indication.
(5) Divide the measured value of one tone by the other to determine the voltage
ratio. If calculated ratio is not between 0.99950 and 1.00050, perform b (1) through (3)
below.
