December 1966 Popular Electronics
Table of Contents
Wax nostalgic about and learn from the history of early electronics. See articles
published October 1954 - April 1985. All copyrights are hereby acknowledged.
I found this Bridge Circuit
Quiz in my stack of vintage Popular Electronics magazines (I thought all had
been posted). I just
ordered another batch of Popular Electronics on eBay, so that will provide a dozen or
so more quizzes. Your challenge here, compliments of Robert P. Balin, is to decide
what the main function of each type of bridge circuit is. Most bridge circuits are designed
such that a component of unknown value is inserted into one of its four branches, and
then one or more variable components of known values are adjusted to balance the bridge
and thereby create a minimum (null) between opposite (circuit-wise) nodes. Admittedly,
I did not fare well, but it is because I do not recall having the names associated with
many of these
bridge circuits. Of course nearly everyone is familiar with the Wheatstone, Kelvin,
and Wien bridges. Hyperlinks are provided to information on the bridge circuit theory.
I could not find any specific page for Mr. Resonance's bridge, but interestingly
many of the pages Google returns has to do with the
Tacoma Narrows Bridge (Galloping Gertie) self-destruction due to resonance.
Bridge Circuit Quiz
By Robert P. Balin
Most electronic technicians are familiar with
the widely used Wheatstone bridge. But many are not so familiar with other types of bridges
commonly used in the laboratory for measurement of impedance-resistive, reactive, inductive,
or capacitive - at frequencies well up into the UHF band. Bridges employ the so-called
null method to measure an unknown quantity, either directly or by computation. In the
latter case, values of some of the fixed and adjustable components in the bridge are
substituted in an applicable equation, which is then solved for the unknown quantity.
See how many circuits (A-J) you can identify by name (1-10).
See answers below.
Popular Electronics published many quizzes over the years
- some really simple and others not so simple. Robert Balin created many of the quizzes.
This is a listing of all I have posted thus far.
Angle Quiz - September 1967
International Electronics Quiz - July 1967
- Bridge Circuit
Quiz -December 1966
- Diode Function
Quiz - August 1965
- Diagram Quiz, August
- TV Trouble Quiz,
- Electronics History Quiz,
- Scope-Trace Quiz,
Circuit Analogy Quiz, April 1973
Your Knowledge of Semiconductors, August 1972
- Ganged Switching
Quiz, April 1972
- Lamp Brightness
Quiz, January 1969
- Lissajous Pattern Quiz, September 1963
Quizoo, October 1962
- Electronic Photo Album Quiz, March 1963
- Electronic Alphabet Quiz, May 1963
- Quiz: Resistive?
Inductive? or Capacitive?, October 1960
- Vector-Circuit Matching Quiz, June 1970
Quiz, September 1961
- RC Circuit
Quiz, June 1963
- Diode Quiz,
- Electronic Curves Quiz, February 1963
- Electronic Numbers Quiz, December 1962
- Energy Conversion Quiz, April 1963
Function Quiz, June 1962
- Electronics Metals Quiz
- October 1964
Electronics Measurement Quiz - August 1967
- Meter-Reading Quiz,
Geometry Quiz, January 1965
Factor Quiz, November 1966
Math Quiz, November 1965
- Series Circuit Quiz,
Electrochemistry Quiz, March 1966
- Electronic Analogy
Quiz, November 1961
Coupling Quiz, August 1973
- Electronics Analogy Quiz, August 1960
- Audio Quiz,
Unit Quiz, May 1962
Capacitor Circuit Quiz, June 1968
- Quiz on AC Circuit Theory, December 1970
- Magnetic Phenomena Quiz, February 1962
- Electronics Geography Quiz, April 1970
Electronic Menu Quiz, August 1963
- Electronic Noise Quiz, August 1962
- Electronic Current Quiz, October 1963
- Electronic Inventors Quiz, November 1963
Function Quiz, January 1962
- Electronic Measurement Quiz, January 1963
Tube Quiz, February 1961
- Kool-Keeping Kwiz, June
1 - J The Carey Foster bridge measures capacitance in terms of mutual
conductance, and mutual conductance in terms of capacitance.
2 - H The Hay bridge measures the self-inductance of high-Q coils (Q greater
than 10), and also determines unknown frequencies.
3 - D The Heaviside bridge measures the mutual inductance of the coils
of a transformer in terms of a known self-inductance and known resistances.
4 - I The Kelvin bridge is used when extremely low resistances - down
to 0.001 ohm - are to be measured.
5 - C The Maxwell bridge measures the self-inductance of low-Q coils (Q
of 10 or less).
6 - F The Owen bridge, like the Hay and Maxwell bridges, measures the
self-inductance of coils. The main difference between the Owen and the other two bridges
is that the Owen bridge has the two adjustable components in the same arm.
7 - A The Resonance bridge measures capacitance, inductance, and frequency.
8 - G The Schering bridge measures capacitance in terms of a standard
capacitor and known resistances.
9 - B The Wheatstone bridge, oldest of the bridge family, is used where
accurate resistance measurements - in the range of 1 ohm to approximately 1 megohm -
are to be made.
10 - E A Wien bridge is used to measure capacitance by comparison with
a standard capacitor, and inductance by comparison with a standard inductor.
Posted June 22, 2018