Electronics World articles Popular Electronics articles QST articles Radio & TV News articles Radio-Craft articles Radio-Electronics articles Short Wave Craft articles Wireless World articles Google Search of RF Cafe website Sitemap Electronics Equations Mathematics Equations Equations physics Manufacturers & distributors LinkedIn Crosswords Engineering Humor Kirt's Cogitations RF Engineering Quizzes Notable Quotes Calculators Education Engineering Magazine Articles Engineering software RF Cafe Archives Magazine Sponsor RF Cafe Sponsor Links Saturday Evening Post NEETS EW Radar Handbook Microwave Museum About RF Cafe Aegis Power Systems Alliance Test Equipment Centric RF Empower RF ISOTEC Reactel RF Connector Technology San Francisco Circuits Anritsu Amplifier Solutions Anatech Electronics Axiom Test Equipment Conduct RF Copper Mountain Technologies Exodus Advanced Communications Innovative Power Products KR Filters LadyBug Technologies Rigol TotalTemp Technologies Werbel Microwave Windfreak Technologies Wireless Telecom Group Withwave RF Cafe Software Resources Vintage Magazines RF Cafe Software WhoIs entry for RF Cafe.com Thank you for visiting RF Cafe!
Temwell Filters

LadyBug RF Power Sensors

withwave microwave devices - RF Cafe

Please Support RF Cafe by purchasing my  ridiculously low−priced products, all of which I created.

RF Cascade Workbook for Excel

RF & Electronics Symbols for Visio

RF & Electronics Symbols for Office

RF & Electronics Stencils for Visio

RF Workbench

T-Shirts, Mugs, Cups, Ball Caps, Mouse Pads

These Are Available for Free

Espresso Engineering Workbook™

Smith Chart™ for Excel

Copper Mountain Technologies (VNA) - RF Cafe

What's Your EQ?
March 1967 Radio-Electronics

March 1967 Radio-Electronics

March 1967 Radio-Electronics Cover - RF Cafe[Table of Contents]

Wax nostalgic about and learn from the history of early electronics. See articles from Radio-Electronics, published 1930-1988. All copyrights hereby acknowledged.

These two circuit analysis challenges from the March 1967 issue of Radio−Electronics magazine were simple enough that even I figured them out on the first try. The first one requires simply summing currents given the stated resistor and voltage values. For the second problem, note the configuration is that of an autotransformer, then used the provided load current and voltage to work it out based on power out versus power in. That should make it a cinch for anyone else, too. I'm glad there was no "black box" type problem in this set, since those take too much thinking, and my solutions rarely match the author's, and I end up feeling like an idiot. Bon chance.

What's Your EQ?

50 Years Ago March 1917 Radio Electronics - RF CafeWhat's Your EQ?, March 1967 Radio-Electronics - RF CafeConducted by E. D. Clark

Two puzzlers for the student, theoretician and practical man. Simple? Double-check your answers before you say you've solved them. If you have on interesting or unusual puzzle (with an answer) send it to us. We will pay $10 for each one accepted. We're especially interested in service stinkers or engineering stumpers on actual electronic equipment. We get so many letters we can't answer individual ones, but we'll print the more interesting solutions-ones the original authors never thought of.

Write EQ Editor, Radio-Electronics, 154 West 14th Street, New York, N. Y. 10011.

Transistor current - RF CafeTransistor Current

In the circuit illustrated, forward bias (base-emitter and base-collector) is 0.5 volt. Is IB (1) greater than IE, (2) smaller than IE, or (3) equal to IE?

- Allan C. Schoening

 

Current mystery - RF CafeCurrent Mystery

In the circuit to the right, the fuse does not blow. Why not?

- Clarence L. Chinn

 

[Answers at bottom of page]


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

These are the answers.

Transistor Current Solution - RF CafeTransistor Current

Correct answer is (1), for IB is greater than IE. Here's how to figure the currents:

 

 - RF CafeCurrent Mystery

That portion of the autotransformer winding from B to C appears to the load as a separately wound secondary. Thus the 6-amp current flows only like this:

Section B to C, however, is also a portion of the primary winding, section A to C. The load requirement is 36 watts. Since the complete primary has 117 Vac across it, primary current is only 308 mA (assuming no losses in the autotransformer).

 

 

Posted March 29, 2024

DC-70 GHz RF Cables - RF Cafe

About RF Cafe

Kirt Blattenberger - RF Cafe Webmaster

Copyright: 1996 - 2024

Webmaster:

    Kirt Blattenberger,

    BSEE - KB3UON

RF Cafe began life in 1996 as "RF Tools" in an AOL screen name web space totaling 2 MB. Its primary purpose was to provide me with ready access to commonly needed formulas and reference material while performing my work as an RF system and circuit 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 while tying up your telephone line, and a nice lady's voice announced "You've Got Mail" when a new message arrived...

Copyright  1996 - 2026

All trademarks, copyrights, patents, and other rights of ownership to images and text used on the RF Cafe website are hereby acknowledged.

All trademarks, copyrights, patents, and other rights of ownership to images and text used on the RF Cafe website are hereby acknowledged.

My Hobby Website: AirplanesAndRockets.com

My Daughter's Website: EquineKingdom



Exodus Advanced Communications Best in Class RF Amplifier SSPAs

TotalTemp Technologies (Thermal Platforms) - RF Cafe