415 kHz: +2 volts
455 kHz: 0 volt
495 kHz: -2 volts
The diagnosis of the circuit under test should state that the
a. limiter is not functioning properly and resistor R18 must be adjusted.
b. linearity of the discriminator is poor and the inductance tuning slug in
the primary of T6 must be adjusted.
c. discriminator must be tuned to the correct center frequency by adjusting
the capacitor in the secondary of T6.
d. tuned circuits are operating normally with respect to linearity and center
frequency alignment.
10. At one stage of the alignment of the FM receiver shown in figure 152 of TM
11-668, an FM signal generator is connected to the control grid of V6, and the
vertical plates of the oscilloscope are connected across R7.
The oscilloscope
screen is represented by figure 4-6, in which the solid line represents the actual
response and the dotted line shows the ideal response. The component that should
be adjusted to obtain the correct response is
a. the capacitor in the plate circuit of V6.
b. the capacitor in the secondary of T3.
c. capacitor C32.
d. resistor R12.
11. When aligning the secondary of the ratio detector in the receiver shown in
figure 152 of TM 11-668, a signal generator set to the correct IF is connected to
the grid of V6. A VTVM is then connected
a. across R12, while C32 is adjusted to give maximum deflection of the meter.
b. across the secondary of
T4,
while
R12
is
adjusted
to
give
maximum
deflection of the meter.
c. from the junction of R6 and C20 to the junction of two equal resistors
connected across R12, while C32 is adjusted to give zero meter deflection.
d. from the junction of R6 and C20 to ground, while R12 is adjusted to give
zero meter deflection.
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