User's Manual Part 2

Linearity Equalization Circuitry
After the filtering circuitry a linearity equalization circuit can be placed in the signal path to
compensate for nonlinear distortions that may appear at a later stage in the transmission
system. These distortions are the result of gain compression in high power amplifier stages.
The linearity equalization circuit will offset gain compression by increasing signal gain
through the module as the signal increases in power. This will maintain a more consistent
gain through the system.
The linearity equalization circuit can be placed in the signal path by selecting the IN position
with the toggle switch SW1 on the front of the module. The amount of equalization can be set
through CUT-IN and MAGNITUDE potentiometer on the front of the module as described
below.
Output Gain Circuitry
The IF output signal is applied to the backplane board connection J1-1B the DIN connector
located at the rear of the module. The output range is selected with O/P gain jumper J26
and J27.
A sample of the IF output signal is provided on the front of the module through a directional
coupler placed before the O/P gain selection circuitry.
41
Potentiometer Operation
Cut in R64 Sets the signal level at which the equalizer circuit begins to increase the signal
gain
Mag R65 Sets how much the signal gain will increase through the module
Gain Jumper Settings Output Range
HI gain -13 to -3 dBm PEP
LO gain -18 to -8 dBm PEP
Gain Jumper Settings Sample Coupling
HI gain -21 dB
LO gain -26 dB