Besides the everyday bands, there is a calendar of temporary operations: stations that appear for a day, a weekend or a month, to mark an event or to activate a place that has no permanent amateur. Chasing them, or running one, is a good way to collect contacts you could not make from a normal station.
Three programs
Each program publishes its own list, dates and rules. Check the current ones before planning.
Special event stations celebrate an anniversary, a festival, a milestone or an organisation. In the US they often use a special event call sign, which is a short-term call sign available for such events; see Vanity and special-event calls. Operators usually offer a certificate for those who contact them, and some publish a way to download or request it.
IOTA groups the world's islands into numbered groups, each identified by a continent code and a number. An operator on an island (or a chaser contacting one) records the group. Awards go to those who collect a range of groups. Islands that are hard to reach, from remote coasts and sandbars to far-flung territories, are favourite expedition targets.
Lighthouse programs list lighthouses (and in some cases lightships and other structures) and encourage operators to contact them from or near the structure. Several organisations run these programs, and a weekend each year draws many activators; check what each one currently offers.
How you take part
As a chaser, watch for announcements and spots. Work the station, log it exactly and, if you want a certificate, follow the instructions to claim it. A special call sign must be copied correctly; ask for it to be repeated.
As an activator, pick a place, check any permission or access requirement, set up a portable station (see Portable and field antennas) and announce your operation in the usual places.
Run a club event. A special event station is a good way for a club to attract visitors and new members.
Things to check
Confirmation. Special event contacts can often be confirmed through the same systems as ordinary ones, such as Logbook of The World. Check each program's own rules for what it accepts. See Logging and QSL confirmations.
Call sign use. An operator must still be licensed, must identify properly and must stay within the license class. A special event call sign does not change those limits.
Fake claims. Look for a program's official list or a trusted announcement. Only a station that actually appears in the program's listing is part of it.
Timing. Many such stations are on for a short period. Plan your chase around the band's openings; see Skywave, hops and the skip zone.