Orban OPTIMOD 6200, Operating Manual

Page: 61 / 195

OPTIMOD INSTALLATION
2-19
If you are using an Orban 4000 Transmission Limiter
If the STL uses pre-emphasis, its input pre-emphasis network will probably
introduce overshoots that will increase peak modulation without any increase
in average modulation. We therefore strongly recommend that the STL trans-
mitter’s pre-emphasis be defeated (freeing the STL from such potential over-
shoot), and that the 4000 be used to provide the necessary pre-emphasis.
If the STL transmitter’s pre-emphasis cannot be defeated, then configure the
4000 for flat output. In this case average modulation levels of the STL may
have to be reduced to accommodate the overshoots.
1. Configure the 4000’s internal jumpers
A)
Remove the top and bottom covers to access the main circuit boards.
Note that the 4000 is a two-channel unit and has two boards with identical
jumpers for resetting.
B)
Refer to Figure 2-7 for jumper locations.
JH1
JH2
JF
JG1 JG2 JG3 JJ
JE JC
JB
JD
JA
JI
Figure 2-7: 4000 Jumper Locations