[Milsurplus] countermeasure against proximity fuse

[Ray Fantini]

According to the "Graphic Survey of Radio and Radar Countermeasures Equipment "(Y-109829) from back in February of 1945 several items were available for airborne jamming including the AN/APT family that covered 107 to 230 MHz 
The AN/APQ-2, 9, and 15 all covered the rest of the band up to around 950 MHz
The AN/APQ-17 is receiver transmitter that according to the book was designed for use in the Pacific Theater for jamming Japanese radar where there was rapid changes between frequencies. The example given is that the early warning radar would be on one frequency but the gun laying radar would be on a second so the operator need the ability on a signal radio to change frequency quickly. The APQ-17 covered from 50 to 220 MHz and developed between 20 to 50 watts.
The AN/APT-1, 2 and 3 were all used for German Freya, Hoarding and Wasserman radar and would also be affective on the Japanese early warning radar. The AN/APT-4 would cover up to 770 MHz and was effective on the German Rhubarb, Liechtenstein and Wurzburg radars. There is lots of information on the APR-4, ARR-5 and ARR-7 along with several systems that were intended for jamming communications with my favorite being the TU-60 that is a tuning unit that fits into a BC-191 or BC-375 that makes it into a Barrage jammer to knock out communications in the 15 to 20 MHz band. Imagine what fun that would be to play with but there is not a signal word about receiving or attempting to jam proximity fuses anywhere in the book.  
Forget where I downloaded this book but think it was unclassified back in June of 1965.
If you Google the title you can find and download it and learn everything you ever wanted to know about WW2 state of the art countermeasures.

Ray F/KA3EKH