control settings of each of the equalizer sections.
Use the FREQUENCY
readout of the TS-2669/GCM for selection of carrier frequency. Adjust the
DELAY control of each corresponding equalizer section so that the delays at
all the selected carrier frequencies are approximately equal as read on the
DELAY meter. Maximum and minimum expected delays for the various equalizer
sections are shown in figure 2-6.
Figure 2-6.
Typical delay characteristics of individual sections.
(4) Further fine adjustment of each section may be required since
there may be a slight interaction of delay at adjacent frequencies. After
adjustments are completed, calculate envelope-delay-distortion.
(5) When the 340B is used for this test, the FREQUENCY kHz readout
shows the carrier frequency, while the DELAY USEC readout indicates the
delay.
(6) The circuit conditioner will find that the variation in delay
allowed by the envelope-delay-distortion parameter is less between certain
stated frequencies in the band of interest than at other frequencies. His
work in this area of minimum variation must be performed with greater
precision because he is allowed less margin. He must look carefully at the
stated parameter to determine the frequency band across which his work will
be the most critical.
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