9. Upon completion of equalizing circuit A, the results are shown by the set
of curves in figure 4-7. By analyzing these curves, the circuit conditioner
can see that the
a. curve of the inserted network is identical in every way with that of
the uncorrected circuit.
b. sum of delays of the inserted network and the uncorrected circuit
varies with each test frequency.
c. delays in the corrected circuit all have the same value as shown by
the straight-line characteristic.
d. difference between delays at each frequency always equals zero.
10. Circuit parameters for specified services are published by DCA.
The
parameters which specify limits of envelope delay relate
a. phase end delay.
c. amplitude and phase.
b. delay and frequency.
d. frequency and amplitude.
11. Assume that the parameters specified for circuit B include the following:
1.5 to 2.5 ms between 1,000 and 2,000 Hz. Will it be necessary to condition
this circuit further?
a. Yes, because the uncorrected circuit
and
inserted
network
characteristics are not mirror images.
b. Yes, because the envelope delay of the uncorrected circuit is not
linear with respect to frequencies above 2,000 Hz.
c. No, because no delays anywhere in the characteristic
of
the
uncorrected circuit fall outside the 1.5- to 2.5-ms range.
d. No, because the characteristic of the uncorrected circuit shows that
the circuit parameters are within requirements.
12. Assume that the input level at 1,000 Hz to the combination equalizer shown
in figure 4-4 is -16 dbm, the output level needed is +5 dbm, and the total loss
through the equalizer sections amounts to 10 db.
How much of the 25-db
amplifier gain must be utilized?
(Disregard losses in the input and output
a. l0 db
c. 21 db
b. 16 db
d. 25 db
13. One type of combination equalizer contains 12 equalizer sections. When a
line has been properly equalized for amplitude-frequency distortion as well as
envelope delay, the technician will find that
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