Unit 4 — Operating Procedures and Calculations
TM-GEAR-006 — Open Handout TM Chapters: Chapter 5, Appendix A ELOs: Install and operate the MOTORIZED COIL WINDER — ESP32 CONTROLLER correctly; interpret performance data; compute derived quantities Estimated time: 30 minutes (includes 3–4 practice problems)
Step 1: Read the TM
Open TM-GEAR-006. Read Chapter 5 — Operating Procedures and Appendix A completely.
Then come back here.
Chapter 5 Content
- Home the traverse axis: press HOME button. Traverse moves to minus limit switch and sets position to zero.
- Enter winding parameters via encoder: wire gauge (AWG), turns, coil length (or pitch), wind direction (CW or CCW looking at spindle).
- Press START. The controller winds the specified turns, counting on the OLED display. Press PAUSE to stop at any point; press RESUME to continue.
- After completion: the controller stops and displays DONE + final turn count. The completed program is logged to the SD card with date, wire gauge, turns, and any errors.
- For multi-layer coils: increment the layer counter in the program. The traverse will reverse direction automatically for each layer.
Appendix A — Reference Formulas
| AWG | OD bare (mm) | OD insulated (mm) | Max current (A) |
|---|---|---|---|
| 14 | 1.628 | 1.95 | 15 |
| 18 | 1.024 | 1.30 | 7 |
| 22 | 0.644 | 0.85 | 3 |
| 26 | 0.405 | 0.55 | 1 |
| 28 | 0.321 | 0.45 | 0.5 |
| 30 | 0.255 | 0.35 | 0.3 |
Key Formulas Summary
Key mathematical relationships from Appendix A:
(See Appendix A in the TM)
Operating Notes
Chapter 5 specifies 5 operating steps.
Installation and operating discipline: - Always verify polarity and orientation before making connections — RF transformers and baluns are phase-sensitive - Route feedlines away from parallel conductors — parallel runs create mutual coupling that degrades isolation - Ground all exposed metalwork at a single chassis point — multiple grounds create loops - Record settings, frequencies, and power levels for every test — you need baseline data for comparisons
Practice Problems
Work these before reading the answer key below.
P4-1. Using the operating procedure from Chapter 5 and the formulas from Appendix A: State the installation steps you would take to put the MOTORIZED COIL WINDER — ESP32 CONTROLLER in service on a 40m (7.150 MHz) station. List steps in order.
P4-2. From Chapter 5: what installation or setup detail produces the best RF performance with the MOTORIZED COIL WINDER — ESP32 CONTROLLER? What is the tradeoff if you omit or shortcut that step?
P4-3. Chapter 5 specifies an operating procedure for a specific use case. State the first three steps of that procedure from memory.
P4-4. Appendix A gives a formula for computing a result from measured values. Pick one formula and compute a worked example using made-up but realistic values. Show all work.
Answer Key — Practice Problems
P4-1. Compare your list to Chapter 5. Steps should include: select mounting location → connect to feedline/antenna → verify polarity/orientation → apply power or signal → verify operation → record baseline.
P4-2. See Chapter 5. The most important installation detail is usually physical orientation, lead length, or ground bonding — the tradeoff if omitted is degraded isolation, increased SWR, or common-mode current leakage.
P4-3. See Chapter 5, steps 1–3. Copy exactly then close the TM and state from memory.
P4-4. See Appendix A for the formula. Your arithmetic is correct if your result has the right units and is physically plausible.
Checkpoint
Before proceeding: - [ ] You can state the operating procedure from memory (at least the first 5 steps) - [ ] You can compute the derived quantity from Chapter 5 / Appendix A without looking - [ ] You understand what a degraded or unexpected result tells you about the installation
→ Proceed to Unit 5