FCC Commercial Element 8 pool, section 20

Subelement C

Receiving Systems

Section 20

Mixers

820C1

The diagram in Fig. 8C9 shows a simplified RADAR mixer circuit using a crystal diode as the first detector. What is the output of the circuit when no echoes are being received?

A.
60 MHz CW.
B.
4095 MHz CW.
C.
4155 MHz CW.
Correct Answer
D.
No output is developed.

820C1

This question does not yet have an explanation! Register to add one

Tags: none

820C2

In the receive mode, frequency conversion is generally accomplished by a:

A.
Tunable wave-guide section.
B.
Pentagrid converter.
Correct Answer
C.
Crystal diode.
D.
Ferrite device.

820C2

This question does not yet have an explanation! Register to add one

Tags: none

820C3

An RF mixer has what purpose in a RADAR system?

A.
Mixes the CW transmitter output to form pulsed waves.
Correct Answer
B.
Converts a low-level signal to a different frequency.
C.
Prevents microwave oscillations from reaching the antenna.
D.
Combines audio tones with RF to produce the RADAR signal.

820C3

This question does not yet have an explanation! Register to add one

Tags: none

820C4

In a RADAR unit, the mixer uses a:

A.
Pentagrid converter tube.
B.
Field-effect transistor.
Correct Answer
C.
Silicon crystal or PIN diode.
D.
Microwave transistor.

820C4

This question does not yet have an explanation! Register to add one

Tags: none

820C5

What component of a RADAR receiver is represented by block 49 in Fig. 8A1?

A.
Discriminator.
B.
IF amplifier.
C.
Klystron.
Correct Answer
D.
Crystal detector (the mixer).

820C5

This question does not yet have an explanation! Register to add one

Tags: none

820C6

In a RADAR unit, the mixer uses:

Correct Answer
A.
PIN diodes and silicon crystals.
B.
PIN diodes.
C.
Boettcher crystals.
D.
Silicon crystals.

820C6

This question does not yet have an explanation! Register to add one

Tags: none

Log in

- or -