TM11-5895-846-14
Figure 3-20. LNA Gain/Slope Level.
b.
Overall Receiver Gain
NOTE
The overall receiver gain is calibrated
using signal sources within the
terminal in conjunction with precision
attenuators and a low level SHF hard
limiter as shown in figure 3-21. A
signal at the local receiver frequency
is obtained from the SHF local
oscillator output of the frequency
synthesizer in the upconverter
drawer.
The output level of this
signal is between the limits of + 6 and
+ 12 dBm and is passed through the
SHF hard limiter and attenuator to
provide a -52 dBm signal at the 20 dB
coupler on the AME subassembly,
which gives a nominal -72 dBm signal
at the LNA input.
3-38
