Two Transistor Logic Probe

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.

6 wires to prepare; 195mm total wire, including end allowances.

Parts List

8 unique parts

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2. Cut wires

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

Total wire: 195mm (7.7in)

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 — RED_A — E12 → D12 — 13mm — Red

Cut 13mm.

Wire 2 — PROBE — F9 → H4 — 28mm — Yellow

Cut 28mm. Bend 90° up at 10mm.

Wire 3 — VCC — I7 → C5 — 30mm — White

Cut 30mm. Bend 90° up at 20mm.

Wire 4 — VCC — K7 → E16 — 48mm — Green

Cut 48mm. Bend 90° left at 28mm.

Wire 5 — GND — D18 → I16 — 28mm — Blue

Cut 28mm. Bend 90° up at 18mm.

Wire 6 — GND — B18 → D5 — 48mm — Black

Cut 48mm. Bend 90° right at 38mm.

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.