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Tech Smorgasbord Archives -  17

RF Cafe University"Factoids," "Kirt's Cogitations," and "Tech Topics Smorgasbord" are all manifestations of my rantings on various subjects relevant (usually) to the overall RF Cafe theme. All may be accessed on these pages:

 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35 | 36


(source: IEEE Spectrum)

RF Cafe: Nipper, the RCA DogNipper was a stray fox terrier mix that gained a spot in electronics history as the symbol of RCA. Nipper was chosen as a model for Francis Barraud's painting entitled "His Master's Voice" (which was originally titled, "Dog Looking at and Listening to a Phonograph"). In fact, Nipper would sit at the horn of Barraud's Edison cylinder phonograph with his head cocked, just like in the painting. Nipper appeared on every RCA Victor record label from 1929 until 1969. A few years ago, Melanie bought a Victrola music box, which I figured needed its own RF Cafe: Nipper the RCA dogNipper to be complete. Here is what we came up with.



Oil Loss in New Cars

(source: Popular Mechanics)

While it has nothing to do with electronics, I ran across a surprising (to me) article regarding oil consumption in new cars. Industry-wide specs claim that 1 quart per 600 to 1,000 miles is the norm. That accounts for blow-by past piston rings, seepage past valve guides, or other means. Catalytic converters prevent the old tell-tale bellowing of blue smoke due to oil burning, so in newer cars it is not as apparent. The topic came up when the owner of a 2007 Toyota Solara complained that his engine was going through a quart every 2,000 miles. My 2007 Chevy Cobalt (2.2L, 34 mpg) loses almost no oil between 3,000-mile changes. Here is a similar statement on oil consumption.


Males Are Evil - Again

(source: Science News)

Evidently, higher education is a bad thing if your are male. Last year we learned that terrorists are likely to be male electrical engineers - compliments of Oxford U. Now, another esteemed academic study group has determined that men who attend college are more likely to commit property crimes during their college years than their non-college-attending peers. This brilliant piece of research is slated to be presented at the annual meeting of the American Sociological Association.

Perhaps the most significant finding of note is that highly educated social behavior researchers possess a greater than normal propensity to produce studies which find that educated men have a greater than normal propensity for crime.



Good Cents Weight Standards

(source: U.S. Mint, Euro)

U.S. coinage is manufactured to very precise standards, and, even allowing for wear, make very good weight/mass standards when you need to calibrate scales to within about ±1.5%. Here are the official weights. Per scientific methods, three decimal places of precision for U.S. coins implies an accuracy of at least ±5e-4 g (±5e-3 g for Euro coins), but that does not jive with Mint's claim.

Penny* 2.500 g
Nickel 5.000 g
Dime 2.268 g
Quarter 5.670 g
50 € cent 7.80 g
10 € cent 4.10 g
5 € cent 3.92 g
1 € cent 2.27 g

Official weights for other country's coins could not be located

* A penny is 0.750" (¾") Ø.


Princeton 2009 College Survey

(source: The Princeton Review)

Students from 368 colleges of all types were polled for opinions of various aspects of the school. Here are some of the result for engineering colleges. Check yours.

Good Professors

#2 Franklin Olin Coll. of Eng.
#8 Harvey Mudd College

Students Study Most

#1 Mass. Inst. of Tech.
#2 Franklin Olin Coll of Eng.
#3 Calif. Inst. of Tech.
#5 Harvey Mudd College
#7 Harvard
#14 U.S. Coast Guard Acad.
#17 West Point (USMA)
#20 Princeton

Bad Professors

#1 Stevens Inst. of Tech.
#2 U.S. Merchant Marine Acad.
#3 Calif. Inst. of Tech.
#6 Johns Hopkins
#9 Rensselaer Poly. Inst.

Students Study Least

#1 Univ. of Florida
#2 Univ. of Maryland
#3 Univ. of Georgia
#9 Auburn


RF Cafe Breaks the PageRank 5 Barrier!

Ever since Google's emergence as the Web's 800-pound search engine gorilla, achieving a high PageRank value (0-10) has been a cause célèbre. Here is the  base equation, ascertained through a combination of published data and reverse engineering:

 RF Cafe: Google PageRank equation   PR(p_i) = \frac{1-d}{N} + d \sum_{p_j \in M(p_i)} \frac{PR (p_j)}{L(p_j)}

A major component is the ratio of inbound links vs. outbound links. For a site like RF Cafe, where I link to many other sources, it is a real battle to get the ratio to even reach parity. After many years of lingering at PR5, RF Cafe finally has achieved PR6 status! Thanks to all who have linked in and who visit regularly.


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About RF Cafe

Kirt Blattenberger - RF Cafe Webmaster

Copyright: 1996 - 2024


    Kirt Blattenberger,


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.

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