# Vibroplex Bug Dating & Identification

Date a Vibroplex semi-automatic Morse code key ("bug") from its serial number, and identify the model from its physical features. This is the Markdown version of [https://www.bug.date/](https://www.bug.date/), intended for AI agents and text-based clients. Serial number data was compiled by John Elwood, WW7P (SK) from over 3,000 documented keys; model identification data is from Randy Cole, KN6W.

## How to date a Vibroplex bug

1. Read the serial number from the nameplate on the base of the key.
2. Look the number up in the tables below. Most serials fall in the main New York City era sequence.
3. Some serial numbers were reused across eras (NYC vs. Portland, ME). If a number matches more than one table, disambiguate using the nameplate address and model (see "Disambiguating duplicate serials" below).

## Main production sequence (New York City era, 1905–1979)

| Serial range | Year |
|---|---|
| 400 – 1,286 | 1905 |
| 1,287 – 2,777 | 1906 |
| 2,778 – 3,255 | 1907 |
| 3,256 – 6,106 | 1908 |
| 6,107 – 9,999 | No keys reported (gap) |
| 10,000 – 10,399 | 1911 |
| 10,400 – 11,766 | 1912 |
| 11,767 – 12,250 | 1913 |
| 12,251 – 19,999 | No keys reported (gap) |
| 20,000 – 20,621 | 1912 |
| 20,622 – 20,800 | 1913 |
| 20,801 – 24,999 | No keys reported (assumed gap) |
| 25,000 – 25,577 | 1913 |
| 25,578 – 26,154 | 1914 |
| 26,155 – 49,999 | No keys reported (gap) |
| 50,000 – 50,907 | 1913 |
| 50,908 – 51,827 | 1914 |
| 51,828 – 54,231 | 1915 |
| 54,232 – 57,268 | 1916 |
| 57,269 – 60,308 | 1917 |
| 60,309 – 64,573 | 1918 |
| 64,574 – 72,352 | 1919 |
| 72,353 – 80,960 | 1920 |
| 80,961 – 84,681 | 1921 |
| 84,682 – 88,402 | 1922 |
| 88,403 – 91,375 | 1923 |
| 91,376 – 94,316 | 1924 |
| 94,317 – 95,865 | 1925 |
| 95,866 – 99,574 | 1926 |
| 99,575 – 101,339 | 1927 |
| 101,340 – 103,104 | 1928 |
| 103,105 – 103,952 | 1929 |
| 103,953 – 104,800 | 1930 |
| 104,801 – 105,648 | 1931 |
| 105,649 – 106,496 | 1932 |
| 106,497 – 107,344 | 1933 |
| 107,345 – 108,192 | 1934 |
| 108,193 – 109,040 | 1935 |
| 109,041 – 109,888 | 1936 |
| 109,889 – 110,736 | 1937 |
| 110,737 – 111,571 | 1938 |
| 111,572 – 113,865 | 1939 |
| 113,866 – 116,159 | 1940 |
| 116,160 – 118,452 | 1941 |
| 118,453 – 122,536 | 1942 |
| 123,537 – 126,619 | 1943 |
| 126,620 – 137,394 | 1944 |
| 137,395 – 148,169 | 1945 |
| 148,170 – 152,526 | 1946 |
| 152,527 – 156,883 | 1947 |
| 156,884 – 161,353 | 1948 |
| 161,354 – 165,822 | 1949 |
| 165,823 – 170,292 | 1950 |
| 170,293 – 174,762 | 1951 |
| 174,763 – 179,232 | 1952 |
| 179,233 – 183,702 | 1953 |
| 183,703 – 188,172 | 1954 |
| 188,173 – 192,642 | 1955 |
| 192,643 – 197,112 | 1956 |
| 197,113 – 201,582 | 1957 |
| 201,583 – 206,052 | 1958 |
| 206,053 – 210,517 | 1959 |
| 210,518 – 217,034 | 1960 |
| 217,035 – 223,551 | 1961 |
| 223,552 – 230,068 | 1962 |
| 230,069 – 236,585 | 1963 |
| 236,586 – 240,870 | 1964 |
| 240,871 – 245,155 | 1965 |
| 245,156 – 249,440 | 1966 |
| 249,441 – 253,725 | 1967 |
| 253,726 – 258,010 | 1968 |
| 258,011 – 263,874 | 1969 |
| 263,875 – 266,151 | 1970 |
| 266,152 – 267,328 | 1971 |
| 267,329 – 270,152 | 1972 |
| 270,153 – 272,975 | 1973 |
| 272,976 – 373,006 | Only two serials documented; dating uncertain (≈1973–1974) |
| 373,007 – 375,415 | 1974 |
| 375,416 – 378,752 | 1975 |
| 378,753 – 382,089 | 1976 |
| 382,090 – 385,426 | 1977 |
| 385,427 – 386,951 | 1978 |
| 386,952 – 391,230 | 1979 |

## Prefix serial numbers (early production)

| Prefix + range | Year | Model |
|---|---|---|
| D5,015 – D5,310 | 1913 | Double Lever |
| B518 – B1,623 | 1914 | No. 4 |

## Portland, Maine era (1980–1995)

Vibroplex moved to Portland, Maine in 1979 and restarted several parallel serial sequences, so low serial numbers can match both eras.

| Serial range | Year |
|---|---|
| 4,003 – 4,955 | 1980 |
| 5,261 – 5,921 | 1980 |
| 40,000 – 40,787 | 1980 |
| 40,788 – 42,077 | 1983 |
| 42,078 – 49,762 | 1982–1984 (assorted numbers) |
| 49,763 – 51,710 | 1985 |
| 51,711 – 54,163 | 1986 |
| 54,164 – 55,911 | 1987 |
| 55,912 – 60,077 | 1987–1988 |
| 60,078 – 61,963 | 1988 |
| 61,964 – 62,254 | 1988–1989 |
| 62,255 – 65,764 | 1990 |
| 65,765 – 67,132 | 1991 |
| 67,133 – 69,068 | 1992 |
| 69,069 – 70,410 | 1993 |
| 70,411 – 70,778 | 1994 |
| 70,779 – 80,361 | 1994–1995 |
| 80,362 – 80,870 | 1995 |

### Portland "01xxx" series

These serials appear on the nameplate with a leading zero (e.g. 01185).

| Serial range | Year |
|---|---|
| 01,185 – 01,671 | 1983 |
| 01,672 – 02,158 | 1984 |
| 02,159 – 02,645 | 1985 |
| 02,646 – 03,132 | 1986 |
| 03,133 – 03,619 | 1987 |
| 03,620 – 04,106 | 1988 |
| 04,107 – 04,337 | 1988–1989 |
| 04,338 – 05,334 | 1990 |
| 05,335 – 06,439 | 1991 |
| 06,440 – 07,725 | 1992 |
| 07,726 – 07,896 | 1993 |
| 07,897 – 08,205 | 1994 |
| 08,206 – 08,514 | 1995 |

Serial numbers outside all documented ranges may belong to post-1995 keys, special editions, or may be misread.

## Disambiguating duplicate serials

When a serial number matches both the NYC and Portland tables:

- A nameplate reading "Portland, ME" or "Portland, Maine" confirms the Portland era (1979+).
- A nameplate with a New York City address (Broadway, Fulton St.) confirms the NYC era.
- Iambic paddles and Brass Racers were introduced in 1979+, confirming the Portland era.
- The Junior (discontinued 1939) and Blue Racer (discontinued 1966) confirm the NYC era.
- The Lightning Bug and Champion were discontinued in November 1980, so they are almost always NYC era unless the serial is very low (under ~5,000) and the nameplate says Portland.
- The Original has been in continuous production since 1905, so the nameplate location is the deciding factor.

## Models in production by year

| Model | Production years |
|---|---|
| Original | 1905–present |
| Double Lever | 1907–1925 |
| Model X | 1911–1923 |
| Blue Racer | 1914–1966 |
| Upright | 1917–1919 |
| Midget | 1918–1920 |
| Junior | 1920–1939 |
| Lightning Bug | 1927–1980 |
| Champion | 1939–1980 |
| Zephyr | 1939–1958 |
| Presentation | 1948–present |
| Vibro-Keyer | 1960–present |
| Iambic | 1979–present |
| Brass Racer | 1982–present |

## Model identification

First check for distinctive body types:

- **Upright**: U-shaped base, stands vertically. The most collectible Vibroplex model.
- **Midget**: Thin nickel-plated base with an outrigger leg and peg damper. Very scarce.
- **Double Lever**: Two separate levers, each with its own paddle. Hard to find.

For standard-type bugs, identify by damper shape and base width:

| Damper shape | 3.5" base | 3" base | 2.5" base |
|---|---|---|---|
| **"L"** (two cast pieces, L-shaped base, hinged top with wheel) | Original, Double Lever, or Presentation | Junior | Blue Racer (later version) |
| **"U"** (U-shaped casting, wheel on side) | #4 Blue Racer (wide-base, special order) | #4 Blue Racer (wide-base, special order) | #4 Blue Racer |
| **"T"** (vertical post with horizontal arm, wheel at end) | Patent 457, Model X, or early Original/Double Lever | None known | #4 Blue Racer (rare) |
| **"M"** (wheel hangs from bar between two posts) | Lightning Bug | None known | None known |
| **"I"** (U-shaped bent metal holds wheel) | Champion | Zephyr | None known |
| **Simple** (no loosely-mounted wheel) | Improved Model X | None known | Midget (advertised but unconfirmed) |

## Related pages

- [Bug tuning, descratching & maintenance](https://www.bug.date/tuning.md) ([HTML](https://www.bug.date/tuning.html))

## Sources & credits

- Serial number data: [WW7P's Vibroplex dating research](https://radiotelegraphy.net/vibroplexdating.htm), compiled by John Elwood, WW7P (SK) and Randy Cole, KN6W
- Model identification: [vibroplexcollector.net](https://www.vibroplexcollector.net/?page_id=551)
- Damper images: Justin King, KG5VNQ
- Site maintained by Jay, W6JY — jaysvana@gmail.com