Ham radio (Fallout 3)

A ham radio is a small radio transceiver popular among amateur radio enthusiasts.

Background
Amateur radio began as a popular hobby and disaster relief service in the 1940s and 1950s in North America and remained a popular past time up until the Great War. Few radio stations are active by default. Some of the transmitter towers upon which the ham radio stations rely on for range have been shut down but despite the passage of time, many of these units are still functional.

Active transmitter towers are distinguishable by their tall, spindly structure which is easily spotted. Most towers have a transformer station either directly at their bases or nearby. Typically, one of the transformers will have a breaker box attached, or one will be mounted in a control cabinet nearby. Throwing the breaker will reactivate the broadcast.

Ham radios broadcast a signal that serves as a beacon to lead the player character to another location. The signal received by one's Pip-Boy is not sent from the above-ground tower, but rather from the actual ham radio unit itself. These transmitters can be found in various sheltered locations, such as drainage cisterns, tunnels, or caves. The broadcast will become more clear as one moves closer to the ham radio unit and conversely, turns to static and fades out completely as one moved farther away. The player character can turn the ham radio off once they reach it, which stops the broadcast. Ham radios are indestructible and cannot be added to the inventory.

Fallout 3
Ham radio broadcasts:
 * Signal Alfa Lima (AL) [3] - In northwest of the Fallout 3 map, at broadcast tower KB5, just west of deathclaw sanctuary
 * Signal Echo Foxtrot (EF) [4] - Near north edge of map, south of Oasis
 * Signal Kilo Bravo (KB) [1] - Also in northwest, from WKML Broadcast Station, a bit southeast of Signal Alpha Lima and far south of Fort Constantine
 * Signal Oscar Tango (OT) [5] - Perhaps the closest to Megaton, head west-northwest to the Jury Street Metro station; it is a little south of it
 * Signal Oscar Zulu (OZ) [2] - In the northeast of the map, a bit southeast of Relay Tower KX-B8-11 and northeast of Temple of the Union.
 * Signal Papa November (PN) [9] - Due west of Megaton near the west edge of the map, at a tower just west of the Charnel House. Southwest of Fort Bannister and northwest of Evergreen Mills.
 * Signal Sierra Romeo (SR) [6] - On west edge of map at broadcast tower KT8, due north of Little Lamplight and northeast of Vault 87
 * Signal Sierra Victor (SV) [8] - In the southwest of the map, southeast of Jocko's Pop & Gas Stop.
 * Signal Yankee Bravo (YB) [7] - In the northeast of the map, just south of Canterbury Commons.
 * One is set up as part of the public-address system in the Super-Duper Mart. Raiders using the store as a base use the PA system to alert others in the building.
 * Chinese technicians use ham radios to call for backup inside the Chinese listening post.

Fallout: New Vegas

 * One ham radio at a lookout point on Guardian Peak.
 * Radios in the Sierra Madre can be targeted and destroyed, unlike normal ham radios, because they broadcast a decayed frequency which can detonate bomb collars.

Fallout 4

 * Relay tower 0BB-915