Ever wonder why transistors have “2N” part numbers?

This from Wikipedia:

The JEDEC Solid State Technology Association, formerly known as the Joint Electron Device Engineering Council (JEDEC), is an independent semiconductor engineering trade organization and standardization body.

The early work began as a part numbering system for devices which became popular in the 1960s. The first semiconductor devices, such as the 1N23 silicon point contact diode, were still designated in the old RMA tube designation system, where the “1” stood for “No filament/heater” and the “N” stood for “crystal rectifier”. The first RMA digit thus was re-allocated from “heater power” to “p-n junction count” to form the new EIA/JEDEC EIA-370 standard; for example, the 1N4001 rectifier diode and 2N2222 transistor part numbers came from EIA-370. They are still popular today. In February, 1982, JEDEC issued JESD370B, superseding the original EIA-370 and introducing a new letter symbol “C” that denotes the die version, as opposed to “N”, now meaning the packaged version. The Japanese JIS semiconductor designation system employs a similar pattern. JEDEC later developed a numbering system for integrated circuits, but this did not gain acceptance in the semiconductor industry. The European Pro Electron semiconductor numbering system originated in a similar way from the older Mullard–Philips tube designation.

Earlier in the 20th century, the organization was known as JETEC, the Joint Electron Tube Engineering Council, and was responsible for assigning and coordinating RETMA tube designations to electron tubes (also called valves). The type 6L6, still to be found in electric-guitar amplifiers, typically has a type number that was assigned by JETEC.

JEDEC also developed a number of popular package drawings for semiconductors such as TO-3, TO-5, etc. These are on the web under JEP-95.

Thanks for Karl, W4KRL, via the AMRAD Tacos mailing list for this factoid.