Garmin GNC 255, Installation Manual

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GTR 225/GNC 255 TSO Installation Manual 190-01182-02
Page 1-6 Rev. B
1.3.7 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 when:
• the level of a standard glideslope deviation test signal
produces 50% or less of standard deflection of the deviation
indicator.
• 150 Hz modulation is absent.
• 90 Hz modulation is absent.
• 90 Hz and 150 Hz modulations are both absent.
• RF signals are absent.