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A 6 dB pad between the Jamming Carrier Loop output of the EE-2002 and
the IF input of the modulator will usually lower the overall power
presented to the output mixer of the modulator sufficiently to prevent the
distortion.
The same effect may be viewed upon a spectrum analyzer that is
displaying the entire channels output bandwidth and looking for Spurs
which present themselves only with the inclusion of the jamming carriers.
5.2 Distortions Outside the Encoded Channel
In some cases the distortions generated by the output mixer of the
modulator are of sufficient magnitude as to affect other channels within
the system. The same remedy as implemented above will return the
modulator to a clean output.
There is one instance where the distortion is not generated by the
marriage of the EE-2002 to the modulator. This is where the distortion is
formed within the Television Receiver itself. You can easily distinguish
this distortion from others due to the fact that it occurs only in a non-
subscriber, and the placement of a decoding filter prior to the sets input
will remove the distortion on adjacent channels.
This distortion is occurring due to the fact that the TVs IF filter is
allowing the jamming carriers to blow through to the demodulation
circuitry. The remedy for this problem is the placement of a positive and a
negative filter on that subscribers drop to eliminate the jamming carriers
and notch out the visual carrier to prevent the reception of the channel, or
the placement of a special CV filter for that channel which accomplishes
the same end result by lowering both the jamming carriers and the visual
carrier by approximately 15 dB.
6.0 APPLICATION NOTES
The following application notes cover two alternate technologies for the
delivery of premium channel programming and how they may affect the
traditional set-up of the EE-2002 encoder.
6.1 MMDS Operation ( Single Jamming Carrier Operation )
In an MMDS or single channel microwave delivery technology the
primary transmitter intended to deliver the visual content of the channel
has insufficient output capability to handle the additional energy of the
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