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.
Test your diode switch analysis
skills here with six circuits designed by Mr. Robert P. Balin in the July 1961 issue
of Popular Electronics. When evaluating the equivalent circuits with the diodes
biased on or off, don't make the job more difficult for yourself by considering
whether there is enough voltage or current to turn a particular diode on or not,
just whether the diode is forward or reverse biased. Doing so reduces everything
to simple series and parallel combinations. Redrawing each circuit either with a
short for a forward biased diode and an open for a reverse biased diode makes the
task easier.
If you like diode quizzes, here is another from the August 1965 issue of
Popular Electronics.
Diode Quiz
By Robert P. Balin
Keeping in mind that a diode can pass current in one direction only, see if you
can find the effective resistance across the battery in the circuits below. Assume
that every resistor measures six ohms, and that the diodes have zero resistance
in the forward direction, infinite resistance in the reverse direction.
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 began life in 1996 as "RF Tools" in an AOL screen name web space totaling
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design engineer. The World Wide Web (Internet) was largely an unknown entity at
the time and bandwidth was a scarce commodity. Dial-up modems blazed along at 14.4 kbps
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