Final Assessment — NEC ANTENNA MODELING SYSTEM

TM-TOOL-003 — Open Handout Course: TM-TOOL-003 Reference: TM-TOOL-003 handout Questions: 15 Passing score: 13/15 (87%). All calculation questions (Q6–Q9) must be correct. Time limit: 20 minutes Notes: Closed handout. No references during the assessment.

Questions

Q1. What is the operating principle of the NEC ANTENNA MODELING SYSTEM? State it in one sentence using technical terms.

Q2. 2-1 NEC Card Format Summary Explain the significance of this principle for measurement accuracy.

Q3. What is the primary source of measurement error for the NEC ANTENNA MODELING SYSTEM as stated in Chapter 2? What operating technique minimizes this error?

Q4. Chapter 3 specifies particular component types for the NEC ANTENNA MODELING SYSTEM. Name two components where a wrong substitution would degrade RF performance and explain why.

Q5. What is the first step of the Chapter 4 assembly procedure? Why must assembly steps be performed in the specified order?

Q6. [Calculation] Using the formula from Appendix A (| Impedance = 0+j0 | Source on wrong tag/segment | Verify EX card tag matches GW tag |): Apply it to a realistic scenario with the NEC ANTENNA MODELING SYSTEM. Show all work and state the result with units.

Q7. [Calculation] Using the formula: a second formula from Appendix A Calculate a result for a specific measurement. Show all work.

Q8. [Calculation] During a measurement with the NEC ANTENNA MODELING SYSTEM, you observe a reading of X. The expected (reference) value is Y. Compute the error in % and in appropriate units. (Use X = your measured value from the Unit 5 lab; Y = the acceptance criterion.)

Q9. [Calculation] The Chapter 5 operating procedure requires a specific numerical computation to interpret a measurement. State the formula and solve it for a given set of inputs. Show all work.

Q10. What does Chapter 5 specify as the correct action if a measurement produces an unexpected result during normal operation?

Q11. What is the acceptance criterion stated in Chapter 7 for the NEC ANTENNA MODELING SYSTEM? State it exactly: value, units, and condition.

Q12. What is the difference between the Chapter 6 calibration procedure and the Chapter 7 verification procedure? Which permits adjustments?

Q13. During Chapter 7 verification, one check fails. You make an adjustment and re-check. Is this acceptable? What is the correct action per the TM?

Q14. List four items required in a calibration log entry per Chapter 7.

Q15. After completing Chapter 7 verification, all checks pass. What conclusion can you draw about the NEC ANTENNA MODELING SYSTEM? What conclusion can you NOT draw?

— Turn page for answer key —

Answer Key

All answers directly verifiable from TM-TOOL-003.

A1. See TM §2-1. The answer is the first substantive statement of Chapter 2. TM ref: §2-1

A2. See TM §2-1. The significance is in the paragraph following the principle statement. TM ref: §2-1

A3. See Chapter 2. The error source is identified by words like "dominant," "primary," or as the first-listed limitation. TM ref: Ch. 2

A4. See Chapter 3. Look for items where the TM specifies "non-inductive," a specific ferrite material, or a minimum tolerance — these are where substitutions matter most. TM ref: Ch. 3

A5. See Chapter 4, step 1. The reason for sequence is usually stated in the introductory paragraph of Chapter 4 or implied by the physical dependencies between steps. TM ref: Ch. 4, step 1

A6. Formula: | Impedance = 0+j0 | Source on wrong tag/segment | Verify EX card tag matches GW tag |. Any physically plausible input values give a correct answer if the computation is done correctly. TM ref: App. A

A7. Formula: a second formula from Appendix A. Show substitution, arithmetic, and result with units. TM ref: App. A

A8. Error (%) = (measured − expected) / expected × 100. Error (units) = measured − expected. TM ref: App. A, Ch. 7

A9. See Chapter 5. The formula and its application are in Chapter 5 or Appendix A. TM ref: Ch. 5, App. A

A10. See Chapter 5. The correct action for an unexpected result is always: stop, diagnose the cause, do not proceed until the discrepancy is explained. TM ref: Ch. 5

A11. Criterion: 5% indicate a segmentation or ground. Check your wording against the TM — units and numeric value must match exactly. TM ref: Ch. 7

A12. Calibration (Ch. 6) allows adjustments to bring the tool within specification. Verification (Ch. 7) confirms the result and allows no adjustments. Calibration permits adjustments; verification does not. TM ref: Ch. 6, Ch. 7

A13. No — making an adjustment during verification invalidates the verification. Correct action: stop verification, return to Chapter 6 calibration, then repeat the full Chapter 7 verification from the beginning. TM ref: Ch. 7

A14. See Chapter 7, final steps. Typical items: date, equipment used, measured values, acceptance criteria, pass/fail determination, operator name. TM ref: Ch. 7

A15. You CAN conclude: the tool is performing within its specified accuracy at this time and under these conditions. You CANNOT conclude: it will remain in calibration indefinitely, or that it was in calibration before this verification. TM ref: Ch. 7

Score Routing

Question → Unit map: Q1–Q3 → Unit 1 (Theory); Q4–Q5 → Units 2–3 (Construction/Assembly); Q6–Q9 → Unit 4 (Calculations); Q10 → Unit 4; Q11–Q15 → Unit 5 (Calibration/Verification).