Lamp Brightness Quiz
January 1969 Popular Electronics

January 1969 Popular Electronics

January 1969 Popular Electronics Cover - RF CafeTable of Contents

Wax nostalgic about and learn from the history of early electronics. See articles from Popular Electronics, published October 1954 - April 1985. All copyrights are hereby acknowledged.

Here is an electronics Lamp Brightness Quiz for you to try, compliments of Popular Electronics magazine. Intuition from experience goes a long way here, but if all else fails you can work out the details of the rectifier circuits to determine which lamp received the most current. Keep in mind that the diode symbols are not LEDs; it is the "A," "B," and "C" symbols inside circles that are the lamps whose brightnesses are being considered. LEDs did exist at the time this quiz was created in 1969, but the circuits would perform differently if in fact LEDs were used for double duty of rectification and illumination. Good luck. Answers are at the bottom.

Lamp Brightness Quiz

Lamp Brightness Quiz, January 1969 Popular Electronics - RF CafeBy Robert P. Balin

The brightness of a lamp operated on a.c. depends on the average current through its filaments during each cycle. A rectifier connected in series or parallel with the lamp can be used to control the current on alternate half cycles. In lamp circuits, current paths and individual lamp brightness may be considerably altered, and some interesting effects produced. To test your ability to analyze lamp and rectifier circuits, try to determine which lamp is the brightest in each of the ten circuits shown here. Assume that the diodes have zero forward resistance and infinite back resistance and that all lamps and supplies are identical.

 

See answers below.


Quizzes from vintage electronics magazines such as Popular Electronics, Electronics-World, QST, and Radio News were published over the years - some really simple and others not so simple. Robert P. Balin created most of the quizzes for Popular Electronics. This is a listing of all I have posted thus far.

RF Cafe Quizzes

Vintage Electronics Magazine Quizzes

Vintage Electronics Magazine Quizzes

 

 

 

 

 

 

 

 

 

 

Lamp Brightness Quiz Answers - RF Cafe

 

 

Posted May 12, 2021
(updated from original post on 9/17/2012)