Aeroflex 2050T SERIES, Руководство по эксплуатации, Страница: 294 / 322

OPTION 006 Avionics
Annex-A-33
VOR waveform depth accuracy
SPECIFICATION
±3% of setting ±0.5% for carrier frequencies up to 400 MHz
Test equipment
Description Minimum specification Example
Modulation meter Freq range to 400 MHz
AM accuracy ±1% of reading
Selectable ILS filter IFR 2305
(1) Connect the test equipment as shown in Fig. A-28.
(2) Set up the test equipment as follows:-
Unit under test
VOR mode
Carrier freq 108 MHz
RF level 7 dBm
SUB depth 0 %
REF depth 0 %
Modulation meter
Freq tune 108 MHz
Function AM
Second function 28
On
(3) With SUB and REF set to 0% measure the residual AM noise. Note the reading.
Residual AM noise depth ____________%
(4) On the UUT select a SUB depth of 30% and a REF depth of 0%. Allow the reading on the
modulation meter to settle and note it.
Measured AM depth ____________%
Actual SDM = Measured AM depth - Residual AM noise
Minimum Actual Maximum
28.60% ______% 31.40%
Ensure that the measured depth is in specification.
(5) Repeat (4) for a SUB depth of 0% and a REF depth of 30%.
Minimum Actual Maximum
28.60% ______% 31.40%
(6) Repeat (4) for a SUB depth of 30% and a REF depth of 30%).
Minimum Actual Maximum
57.70 ______% 62.30%