GE ApexPro TT, Техническое руководство

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6-14 ApexPro™ 2001989-351A
Replaceable parts
Bandpass filters
When an antenna system is designed only with notch filters rather than with the
bandpass filter, the use of multiple notch filters can cause excessive signal loss. In
addition, whenever a new TV station is activated in the vicinity, the antenna system
must be redesigned and corresponding notch filters must be installed.
In general, bandpass filters eliminate the need for notch filters on every channel. They
pass only the channel of interest and reject other channels. The result is fewer parts to
install, significant reduction of signal loss in the desired channel, and no redesign of
the system to accommodate new TV stations.
ApexPro bandpass filter 608-614 MHz
The 608-614 MHz bandpass filter passes channel 37 and rejects all other channels,
except for portions of channels 36 and 38. Continue to use channels 36 and 38 in all
systems and in older antenna systems where multiple notch filters are used.
185A
dB loss in passband dB loss outside of passband Status
3.2 > 30 @ 603, 620 MHz Current