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190-01182-02
GTR 225/GNC 255 TSO Installation Manual
Rev. F
Page 1-8
1.7
Glideslope Specifications
Table 1-8 Glideslope Specifications
Characteristics
Specifications
Sensitivity
-87 dBm or less for 60% of standard deflection
Centering accuracy
0 ±0.01183 ddm or 0 ±10.14 mV
Selectivity
The course deviation is 0 ddm, .0091 ddm when using the
glideslope centering test signal as the RF frequency is varied
17 kHz from the assigned channel
At frequencies displaced by
132 kHz or greater, the input signal
is at least 60 dB down
Standard deflection
With a standard deflection FLY DOWN condition (90 Hz
dominant), the output is -78 mV ±7.8 mV
With a standard deflection FLY UP condition (150 Hz dominant),
the output is +78 mV ±7.8 mV
Flag
The unit flags in the event of any of the following conditions:
• The RF level of a standard glideslope deviation test signal is
such that the deflection of the deviation indicator is less that
50% of the standard deflection
• Absence of 150 Hz modulation
• Absence of 90 Hz modulation
• Absence of both 90 Hz and 150 Hz modulations
• Absence of RF signals