[DARARepeater] TNG Thursday November 27 - No meeting (Thanksgiving)

[Mark Erbaugh]

TNG – Thursday, November 27, 2025 - No meeting (Thanksgiving)

DARA Clubhouse, 6619 Bellefontaine Rd. Dayton, OH 45424.  The meeting begins around 7pm. 

There will be no TNG this week. Stay home and binge on turkey and football.

73,
de Mark, N8ME

License Exam Quiz #346

de Steve, AE8AT 

Thinking about quiz topics, I was struck by what seemed like a massive oversight in the technologies that made our hobby what it is today. Actually, two concepts, although they are related. One is the use of Arabic numbers, and the other is the invention of the decimal point. Imagine expressing 14290 kHz in Roman numerals! Trusting Google, the early versions of our base-10 numerals originated in India sometime between the 1st and 4th century including the number zero. It took until the 9th century for a Persian mathematician Muḥammad ibn Mūsā al-Khwārizmī to write a book that would eventually bring the numerals to Europe. We think of the numbers as Arabic rather than Asian since they arrived in Europe via the Middle East. But since Persia (Iran) is not an Arab country, the name is not accurate. It might have been Fibonacci who helped standardize the use of the Arabic numerals in his books around the year 1200. The decimal point is another interesting technology. When you only concern yourself with he number of livestock or bushels of crop, integers probably do just fine. Another mathematician with a name I will not pronounce, Al-Uqlidisi, published a book around 952 or 953 on decimal fractions. The exact arrival in Europe is difficult to date, but we do have a book that used decimal points by Giovanni Bianchini, an Italian merchant and astronomer, published in the 1440s. Both of these technologies took hundreds of years to move the 2800km (1740 miles) from Mumbai to Tehran, and hundreds more to move from Tehran to Rome (3400km or 2113 miles), using these cities to approximate distance. Now for our quiz questions, which are obviously going to be math problems...

T5B05 Which is equal to 500 milliwatts?
A. 0.02 watts
B. 0.5 watts
C. 5 watts
D. 50 watts

G5C09 What is the capacitance of three 100-microfarad capacitors connected in series?
A. 0.33 microfarads
B. 3.0 microfarads
C. 33.3 microfarads
D. 300 microfarads

E8B06 What is the deviation ratio of an FM phone signal having a maximum frequency swing of plus or minus 7.5 kHz if the highest modulation frequency is 3.5 kHz?
A. 2.14
B. 0.214
C. 0.47
D. 47


Answers:
T5B05 = B
G5C09 = C
E8B06 = A

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