Editing Iowa-class battleship (section)

===Electronics (1943–69)===
The earliest search radars installed were the SK air-search radar and SG surface-search radar during World War II. They were located on the mainmast and forward fire-control tower of the battleships, respectively. As the war drew to a close, the United States introduced the SK-2 air-search radar and SG surface-search radar; the ''Iowa'' class was updated to make use of these systems between 1945 and 1952. At the same time, the ships' radar systems were augmented with the installation of the SP height finder on the main mast. In 1952, [[AN/SPS-10]] surface-search radar and [[AN/SPS-6]] air-search radar replaced the SK and SG radar systems, respectively. Two years later the SP height finder was replaced by the [[AN/SPS-8]] height finder, which was installed on the main mast of the battleships.{{sfn|Garzke|Dulin|1995|pp=141–142}}

In addition to these search and navigational radars, the ''Iowa'' class were also outfitted with a variety of [[Ship gun fire-control system|fire control radars]] for their gun systems. Beginning with their commissioning, the battleships made use of a pair of [[Ship Gun Fire Control Systems#MK 38 Gun Fire Control System|Mk 38 gun fire control systems]] with Mark 8 fire control radar to direct the 16-inch guns and a quartet of [[Ship Gun Fire Control Systems#MK 37 Gun Fire Control System (GFCS)|Mk 37 gun fire control systems]] with Mark 12 fire control radar and Mark 22 height finding radar to direct the 5-inch gun batteries. These systems were upgraded over time with the Mark 13 replacing the Mark 8 and the Mark 25 replacing the Mark 12/22, but they remained the cornerstones of the combat radar systems on the ''Iowa'' class during their careers.{{sfn|Sharpe|1991|p=732}} The range estimation of these gunfire control systems provided a significant accuracy advantage over earlier ships with optical rangefinders; this was demonstrated off [[Truk Atoll]] on 16 February 1944, when the ''New Jersey'' engaged the {{ship|Japanese destroyer|Nowaki|1940|6}} at a range of {{convert|35700|yd|km nmi}} and [[Salvo|straddled]] her, setting the record for the longest-ranged straddle in history.<ref name="straddle">{{cite web |url=https://www.battleshipnewjersey.org/the-ship/full-history/ |title=Full History - USS New Jersey, The World's Greatest Basttleship |date=28 March 2024 |website= Battleship New Jersey |access-date=28 March 2024 |quote=}}</ref>

In World War II, the electronic countermeasures (ECM) included the SPT-1 and SPT-4 equipment; passive electronic support measures (ESM) were a pair of DBM radar direction finders and three intercept receiving antennas, while the active components were the TDY-1 jammers located on the sides of the fire control tower. The ships were also equipped with the [[identification, friend or foe]] (IFF) [[IFF Mark III|Mark III]] system, which was replaced by the [[IFF Mark X]] when the ships were overhauled in 1955. When the ''New Jersey'' was reactivated in 1968 for the Vietnam War, she was outfitted with the ULQ-6 ECM system.{{sfn|Sumrall|1988|pp=115–119}}