What to try — enigma

# WHAT TO TRY — A3-2 Enigma ("Enigma Room Oak")

Open `index.html` in any browser — fully offline, nothing to install, nothing loads from a network. The page is labeled PROTOTYPE, and the oak box at the top states the room's rule: a museum piece, for the joy of it — real secrecy is the Dead Drop's job, not this machine's.

1. **The graded vector (30 seconds, proves the machine is real):** click **"Load the fixture setting"** (rotors I · II · III, rings A·A·A, start A·A·A, UKW-B, no plugs), then type **AAAAA**. The lamps must answer **BDZGO** — the canonical Enigma test vector. If it ever answers anything else, the build is broken, not you.
2. **Feel the reciprocity:** under any settings, type a word and note the lamps' answer. Click **Reset rotors to start positions**, then type the *ciphertext* back in — your original word comes back. Same machine, same settings, both directions.
3. **Watch for the double step:** load the fixture setting, then set the start positions to **A · D · U** (middle rotor D, right rotor U) and press any key three times. The windows go **A D V → A E W → B F X**: the middle rotor steps twice in a row. That's the real machine's famous anomaly, kept deliberately.
4. **Try the SAMPLE daily key:** click **Load the SAMPLE daily key** (it's invented for this page — labeled SAMPLE, not a real historical key sheet). Encrypt a short message, reset the rotors, and decrypt it back. Then change **one** thing — one ring letter, one plug pair — and watch the same message come out completely different.
5. **Break the plugboard on purpose:** type a pair that reuses a letter, like `AV AB`, and apply. The page refuses and says why: a letter pairs at most once. Eleven pairs are refused the same way.
6. **Notice what never happens:** type the alphabet slowly under any setting — no letter ever lights its own lamp. That was the machine's great structural weakness, and it's faithfully here.

Owner-test note: settings changes and **Clear text** reset the rotors to the chosen start positions, so an interrupted message restarts cleanly rather than silently desynchronizing.