Outlined below is a zip code list for Portland. Select a zip code you are interested in to find zip code data on demographics, family, housing, education, transportation, and real estate. See the Portland Zip Code Map.
For other uses, see Volt (disambiguation). The volt (symbol: V) is the derived unit for electric potential, electric potential difference (voltage), and electromotive force.
The conventional volt, V90, defined in 1988 by the 18th General Conference on Weights and Measures and in use from 1990, is implemented using the Josephson effect for exact frequency-to-voltage conversion, combined with the caesium frequency standard.