CET Coding & Classification Systems 2 — Questions and Answers
Question 1: In the EIA color code system, what multiplier does a gold band represent?
- 0.001
- 0.01
- 0.1 (Correct answer)
- 10
Correct answer: 0.1
A gold band in the multiplier position represents a multiplier of 0.1, shifting the base value one decimal place to the left.
Question 2: Which JEDEC prefix letter indicates a small-signal NPN transistor in the 2N series?
- 2N (Correct answer)
- 2P
- 2S
- 2T
Correct answer: 2N
The JEDEC 2N prefix designates a bipolar transistor (both NPN and PNP types) registered with the JEDEC organization.
Question 3: In binary-coded decimal (BCD), what is the decimal value of the code 1001 0011?
- 147
- 93 (Correct answer)
- 83
- 163
Correct answer: 93
In BCD, each 4-bit group represents one decimal digit: 1001 = 9 and 0011 = 3, so the value is 93.
Question 4: Which coding system uses mark and space to represent binary 1 and 0 in serial communications?
- Gray code
- ASCII
- NRZ (Non-Return to Zero) (Correct answer)
- Excess-3 code
Correct answer: NRZ (Non-Return to Zero)
NRZ coding holds a high voltage (mark) for logic 1 and low voltage (space) for logic 0 throughout each bit period.
Question 5: What is the hexadecimal equivalent of binary 1101 1010?
- CA
- DA (Correct answer)
- DB
- CD
Correct answer: DA
Splitting into nibbles: 1101 = D and 1010 = A, giving hexadecimal DA.
Question 6: In the military specification (MIL-SPEC) resistor coding system, what does the letter 'R' indicate in a value like 4R7?
- Reliability level
- Decimal point position (Correct answer)
- Resistance tolerance
- Temperature coefficient
Correct answer: Decimal point position
In MIL-SPEC notation, 'R' serves as the decimal point, so 4R7 means 4.7 ohms.
Question 7: The Gray code sequence after 0111 (decimal 7) is:
- 1000
- 1001
- 1100 (Correct answer)
- 0000
Correct answer: 1100
Gray code for decimal 8 is 1100; in Gray code only one bit changes between consecutive values, so 0111 transitions to 1100.
CET Coding & Classification Systems 2
In the EIA color code system, what multiplier does a gold band represent?