Toolkit
Combined Print Pack
Repair traveler, reference-board sheet, checklists and practical sign-off. Blank forms are learning aids; adapt only through your controlled process.
Repair Traveler
Circuit card assembly — diagnosis & repair record
1 · Incoming failure (ATE / squawk)
| Test / step | Device / net | Measured | Limit (spec) | P/F |
|---|---|---|---|---|
The ticket tells you where to look, not always what is wrong — a flagged part may really be a cracked joint, a fixture pin, or a neighbor loading the net. Verify before replacing.
2 · Visual inspection (under magnification)
Findings / location:
3 · Power-on & rail measurements — current-limited supply
| Rail / net | Test point | Expected (per spec) | Measured | P/F |
|---|---|---|---|---|
| Input | ||||
Expected values are intentionally blank. Fill them per board from your own authorized documentation (test spec / ATP / golden-board sheet / BOM for this revision). Supply current at power-on: (vs expected ___ — high = short/latch-up, near-zero = not starting).
4 · Heartbeat — clock / reset / activity (digital)
| Check | Expected | Observed |
|---|---|---|
| Oscillator / clock | ||
| Reset releases | ||
| Bus / activity |
5 · Diagnosis
Symptom → hypothesis → isolating measurement (half-split / golden-board comparison):
6 · Repair action
| Ref des | Part removed (P/N) | Part installed (P/N · lot) | Procedure (IPC-7711/7721) |
|---|---|---|---|
7 · Root cause
Why did it fail? (A victim part needs its cause found before re-power.)
8 · Verification
Circuit Card Academy · Repair Traveler template. This is generic training scaffolding — follow your facility’s controlled traveler, process specs, and traceability requirements for flight hardware.
Golden-Board Signature Sheet
Record a known-good board, then diff suspects against it
Measure a confirmed-good unit once and keep this sheet with the board’s records. On a failed board, repeat each measurement and compare — the first divergence brackets the fault. Record your measured values here; they are not program data we can supply.
A · Power rails (DC volts)
| Rail / net | Test point | Golden value (V) |
|---|---|---|
Idle supply current:
B · Key-node DC signatures (powered)
| Node / TP | Function | Golden value |
|---|---|---|
C · Diode-mode signatures from ground (power OFF)
Black probe on ground; touch each connector/IC pin. This signature set is the fastest way to localize damage by comparison.
| Pin / net | Golden reading (V) |
|---|---|
D · Dynamic references (oscilloscope)
| Signal | Golden frequency / amplitude | Notes |
|---|---|---|
| Main clock / osc | ||
| Reset timing | ||
| Rail ripple (AC) |
Bench Checklists
ESD/FOD · power-on sequence · first five minutes
A · ESD / FOD pre-work (before the tote is opened)
B · First five minutes (before any powered measurement)
- Read the work order / failure ticket fully — what failed, measured vs. limit, hard or intermittent, history.
- Get the schematic, BOM (this revision), assembly drawing, and test spec. Identify “known good.”
- Inspect under magnification: burns, bulged caps, cracked MLCC/tantalum, cold/cracked joints, bent connector pins, FOD, coating damage, prior rework, missing/wrong/reversed parts.
- Power-off rail checks: fuses by continuity; each rail-to-ground signature (note any dead short before powering in).
- Write down what you expect at each node before you probe.
C · Power-on sequence (current-limited supply)
- Set expected input voltage; set current limit just above expected draw.
- Apply power. Read supply current first — far too high = short / latch-up; near zero = not starting.
- Verify every rail at its test point in dependency order (e.g. 28 V → 5 V → 3.3 V → core). Present, in tolerance, clean on the scope.
- A missing rail: check that regulator’s input first. A sagging rail: regulator weak vs. load heavy — lift the load to decide.
- Digital: confirm clock running → reset releases → bus activity (the power → clock → reset → activity hierarchy).
D · Before you close the job
Generic best-practice checklists for training. Defer to your facility’s controlled procedures and ESD program (ANSI/ESD S20.20) for flight hardware.
Pair this sheet with the auto-generated Training Record — the record reports what the learner did (module completion, quiz scores, drills); this sheet is where a supervisor verifies it and countersigns.
Competency Sign-Off Record
Circuit card repair — demonstrated skills & course completion
A · Demonstrated competencies
| Competency | Shown | Date | Assessor |
|---|---|---|---|
| Safe ESD & FOD handling at a protected workstation | |||
| Reads a schematic end to end (symbols, designators, nets) | |||
| Identifies components & polarity; reads color / SMD codes | |||
| Uses the DMM in all modes; understands in-circuit traps | |||
| Sets up & reads an oscilloscope (rails, clock, reset, ripple) | |||
| Localizes a fault (half-split, golden-board comparison) | |||
| Finds a shorted rail to ground | |||
| Troubleshoots a digital board (power→clock→reset→activity) | |||
| Troubleshoots an analog stage (rails, op-amp DC fingerprint) | |||
| Interprets an ATE / ICT failure ticket; verifies before replacing | |||
| Documents a repair (traveler, root cause, traceable lot #s) | |||
| Aware of IPC-A-610 Class 3, J-STD-001, 7711/7721, coating rework |
B · Course modules complete
This records training completion and demonstrated skill. It is not an industry certification — recognized credentials (e.g. IPC) are issued only through an authorized training program. Keep with the trainee’s qualification file.