Cypher-Plugboard Board - 10-Numeric Variant Design Specification

Status: Draft Project: Enigma-NG Version: v.0.1.0 Associated Hardware Revision: Rev A Last Updated: 2026-08-19 Parent Document: design/Electronics/Cypher-Plugboard/Design_Spec.md

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1. Overview

This document specifies the 10-Numeric variant of the Enigma-NG Cypher-Plugboard Board. It supports the 10-digit numeric-only cipher alphabet (0-9), mirroring Cypher-Input's/ Cypher-Output's own 10-Numeric variant character set.

All three Cypher-Plugboard variants share an identical electrical circuit (connector-only HID / USM mating) and an identical PCB strip (J1/J2 only - see design/Electronics/Cypher-Plugboard/Design_Spec.md). Only the jack field's row count, character layout, and jack quantity differ between variants; the jack field mounts to its own machined metal enclosure (not the PCB), sized to this variant's own 2-row layout - the smallest of the three enclosures.

2. Jack Field Layout

10 plug positions, each with 2 jack sockets (Pass 1, Pass 2) placed immediately next to each other, horizontally. Arranged in 2 rows, top-to-bottom:

Row	Characters	Positions
1	0 1 2 3 4	5
2	5 6 7 8 9	5

Total: 10 positions, 20 jack sockets.

Character order: plain numeric order, left-to-right, top-to-bottom.

3. RefDes Allocation

Jacks are numbered sequentially, row by row (top-to-bottom), left-to-right within each row, with the Pass 1 jack immediately followed by its Pass 2 partner at each position:

Row	Characters	RefDes Range	Qty
1	0-4	J3-J12	10
2	5-9	J13-J22	10

Total: J3-J22, 20 jack sockets.

4. Bill of Materials

RefDes	Specification	MPN	Manufacturer	DigiKey PN	Mouser PN	JLCPCB PN	Alt Supplier + PN	Notes	Footprint Available	Footprint Downloaded	Qty
J3-J22	Switchcraft 12A ("E12A"), 6.35mm (1/4") 2-conductor switched panel-mount jack	12A	Switchcraft	SC1089-ND	502-12A	-	-	Plugboard patch jacks, 10 positions x 2 passes; manually assembled, not part of the JLCPCB PCBA order (no JLCPCB PN); 3/8-32 UNEF-2A threaded bushing	-	-	20

Sourcing status: confirmed 2026-08-19 - Switchcraft 12A, DigiKey SC1089-ND, Mouser 502-12A. Datasheet: design/Datasheets/Switchcraft-12A-datasheet.pdf.