[[File:1943 H2X Radar-French vers.png|thumb|400px|right|French-language diagram of H2X displays and equipment]]
'''H2X''' ("Mickey set", [[Listofficially ofknown Worldas Warthe II electronic warfare equipment|'''AN/APS-15]]''', "BTO" or "Bomb Through Overcast" radar<ref>{{cite web |url=http://www.482nd.org/h2x-mickey |title=How H2X "Mickey" Got its name |website=482nd Bomb Group}}</ref>) was an American [[ground scanning radar]] system used for [[blind bombing]] during [[World War II]]. It was a development of the British [[H2S radar]], the first ground mapping radar to be used in combat.<ref name=Jablonski>{{cite book |last=Jablonski |first=Edward |year=1971 |title=Volume 2 (Wings of Fire), Book I (Kites over Berlin) |url= |work=Airpower |page=49}}</ref> It was also known as the "Mickey set" and "BTO" for "Bomb Through Overcast" radar.<ref>{{cite web |url=http://www.482nd.org/h2x-mickey |title=How H2X "Mickey" Got its name |website=482nd Bomb Group}}</ref>)
H2X differed from the original H2S primarily in its [[X band]] 10 [[GHz]] operating frequency rather than H2S' 3 GHz [[S band]] 3 GHz emissions. This gave H2X higher resolution than H2S, allowing it to provide usable images over large cities which appeared as a single blob on the H2S display. The [[Royal Air Force|RAF]] initially considered using H2X as well, but would instead develop their own X band system, the H2S Mk. III. The RAF system ultimately entered service in late 1943, before the first use of H2X in early 1944.
The desire for even higher resolution, enough to image individual docks and bridges, led to a number of variations on the H2X system, as well as the more advanced [[AN/APQ-7]] "Eagle" system. All of these were replaced in the post-war era with systems customized for the [[jet power]]ed [[strategic bomber]]s that entered service.
