User's Manual Part 2

Group Delay Equalization Circuitry
A set group of delay equalizer circuits can be inserted into the signal path after the ALC
attenuator circuit. These have been designed for improved group delay performance for
certain filtering and channel combining schemes. A description of these circuits are given
below.
Band Pass Filtering Circuitry
Several selections of band pass filters are provided after delay equalization to reduce out of
band products.
40
44 MHz Version
Equalizer Circuit Operation
Delay Equalizer 1 Selected for equalization of digital systems using adjacent or channel combiners
selected with jumper J35 and J36 non adjacent channel combiners as well as analog systems using adjacent
combiners
Attenuation Equalizer 1 Always selected when delay equalizer 1 is selected
selected with jumper J37 and J38
Delay Equalizer 2 Selected for equalization of lumped element band pass filter circuit which
selected with jumper J43 and J44 can also be selected on the module
Delay Equalizer 3 Selected for equalization of analog systems using adjacent or non adjacent
selected with jumper J33 and J34 channel combiners
36 MHz Version
Equalizer Circuit Operation
Delay Equalizer 1 Selected for analog systems using adjacent combiners
selected with jumper J35 and J36
Attenuation Equalizer 1 Always selected when delay equalizer 1 is selected
selected with jumper J37 and J38
Delay Equalizer 2 Selected for equalization of lumped element band pass filter circuit which
selected with jumper J43 and J44 can also be selected on the module
Delay Equalizer 3 Selected for equalization of analog systems using adjacent or non adjacent
selected with jumper J33 and J34 channel combiners
Attenuation Equalizer 3 Always selected when delay equalizer 3 is selected
selected with jumper J33 and J34
Filter Circuit Operation
BPF Used in most analog and digital systems. Delay equalization for this filter
Lumped element band pass filter is activated by selecting delay equalizer 2
SAW (optional) Used in digital systems that require sharper out of band filtering of the
Surface acoustic wave filter IF input
NONE Filtering is bypassed with this option.