10. The various mixer circuits used in frequency conversion in FM receivers offer
varying degrees of noise, gain, and simplicity of construction. Because of their
similarity in construction, a minimum number of additional circuit elements is
required when interchanging the
a. pentagrid converter and pentagrid mixer.
b. triode mixer and dual-triode mixer.
c. diode mixer and crystal mixer.
d. diode mixer and triode mixer.
11. The
type
of
mixer
that
is
capable
of
producing
the
greatest
amount
of
conversion gain
is the
a. diode mixer.
c.
pentode mixer.
b. triode mixer.
d.
pentagrid mixer.
12. Frequency conversion in a superheterodyne receiver may be accomplished by
either a mixer or a converter. In contrast to a mixer that is used to produce the
IF, a converter is characterized by its
a. use of a single electron tube.
b. high gain at high frequencies.
c. use of an electron tube with five grids.
d. resistance to pulling with a strong input signal.
13. The mixer that provides the least amount of conversion gain
is the
a. triode mixer.
c.
crystal mixer.
b. pentode mixer.
d.
pentagrid converter.
14. The local oscillators in most VHF receivers utilize some form of a Colpitts
oscillator because the Colpitts type of oscillator circuit
a. has a broad tuning range.
b. is similar to a crystal oscillator circuit.
c. is immune to supply voltage variations.
d. generates a frequency that is not affected by tube reactances.
15. Assume that a crystal oscillator is to be used as the local oscillator for
the first mixer in a double-conversion FM receiver.
The characteristics of the
crystal oscillator must include
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