Continuity Beeper (NE555, probes in the power path)

1. Prepare

Verify component pinouts against each manufacturer’s datasheet before wiring. Label cut wires with their wire numbers; the same numbers follow them through every stage. Wire colors are written out for black-and-white printing. Custom colors can be named in the wire library.

Progress is saved on this browser for this board revision. Changes to the board or measurements start a new checklist. Printed diagrams are references, not life-size templates.

14 wires to prepare; 380mm total wire, including end allowances.

Parts List

8 unique parts

Links may include affiliate referrals.

2. Cut wires

14 wires · +5mm per end for lead-through

Total wire: 380mm (15.0in)

3. Bend wires

Use the straight-line ruler to mark bend points on the wire before bending. Use the bent shape as a visual reference while bending.

Wire 1 — PIEZO — F26 → E26 — 13mm — Red

Cut 13mm.

Wire 2 — CONT — J15 → H15 — 15mm — Yellow

Cut 15mm.

Wire 3 — OUT — E18 → G11 — 38mm — White

Cut 38mm. Bend 90° up at 8mm. Bend 90° right at 25mm.

Wire 4 — DISCH — K15 → F15 — 23mm — Green

Cut 23mm.

Wire 5 — DISCH — L14 → M9 — 25mm — Blue

Cut 25mm. Bend 90° right at 18mm.

Wire 6 — TIMING — M15 → G15 — 25mm — Black

Cut 25mm.

Wire 7 — TIMING — N14 → F11 — 38mm — Red

Cut 38mm. Bend 90° left at 13mm.

Wire 8 — VCC — J10 → H11 — 18mm — Yellow

Cut 18mm. Bend 90° down at 10mm.

Wire 9 — VCC — I12 → E15 — 28mm — White

Cut 28mm. Bend 90° left at 13mm.

Wire 10 — VCC — D14 → F7 — 33mm — Green

Cut 33mm. Bend 90° right at 18mm. Bend 90° up at 23mm.

Wire 11 — GND — D5 → E11 — 31mm — Blue

Cut 31mm. Bend 90° down at 10mm. Bend 45° down-left at 23mm.

Wire 12 — GND — D12 → I17 — 35mm — Black

Cut 35mm. Bend 90° right at 18mm.

Wire 13 — GND — J18 → L18 — 15mm — Red

Cut 15mm.

Wire 14 — GND — K17 → G26 — 43mm — Yellow

Cut 43mm. Bend 90° left at 28mm.

4. Place wires

Component side. Select a wire to emphasize its route in its own color and highlight its endpoints. Wires follow number order, matching the bend guide and solder checklist.

5. Solder connections

Bottom view: horizontally mirrored. Coordinate names still identify the same physical holes. Highlights mark wire endpoints; wire routes belong on the component side. Check each connection and the listed solder bridges.

Board is horizontally mirrored. Column A is on the right.