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August 1962 Popular Electronics[Table of Contents]People old and young enjoy waxing nostalgic about and learning some of the history of early electronics. Popular Electronics was published from October 1954 through April 1985. All copyrights (if any) are hereby acknowledged.
|Here are other Popular Electronics quizzes:|
RC Circuit Quiz, Jun 1963
Capacitor Circuit Quiz, Jun 1968
- Magnetic Phenomena Quiz, Feb 1962
- Electronics Geography Quiz, Apr 1970
- Electronic Menu Quiz, Aug 1963
- Electronic Noise Quiz, Aug 1962
- Electronic Current Quiz, Oct 1963
- Electronic Inventors Quiz, Nov 1963
- Resistor Function Quiz, Jan 1962
- Electronic Measurement Quiz, Jan 1963
- Vacuum Tube Quiz, Feb 1961
Electronic Noise Quiz Answers
1 - B) Transformer buzz is usually produced by the vibration of loose laminations in the transformer's iron core.
2 - H) Relay chatter occurs when the current value in the relay coil is somewhere between the normal operating value and the drop-out value.
3 - I) Turntable rumble is a low-frequency vibration mechanically transmitted to the phono cartridge pickup by the turntable drive mechanism.
4 - G) Keying chirp is caused by undesirable variations in transmitted frequency when the transmitter r.f. oscillator is keyed.
5 - J) Armature growl is a symptomatic sound made by an armature containing shorted turns when placed on a test-stand device called a "growler."
6 - A) Loudspeaker boom is produced by self-oscillation of the speaker at a low-frequency resonant point.
7 - E) Needle scratch is due to a worn stylus point. Dirt and dust on a record or a defective record can produce the same sound.
8 - C) Tube hiss is due to electron collisions in an irregular electron stream caused by an uneven cathode coating. Although a tape recorder (F) and a car generator (D) will also produce hiss, they are not the correct answers for question 8, but for 9 and 10 which follow.
9 - F) Tape recorder wow is comprised of slow variations in the pitch of recorded sounds caused by irregular slippage or drag in the tape drive mechanism. A turntable (I) with a friction drive will also produce wow sounds, but (I) has already been matched with question 3.
10 - D) Generator whine is due to commutator sparking and changes in frequency with varying engine speeds, and it sometimes interferes with reception in or from mobile stations.
Posted January 31, 2013