Amerikanska dokument från 1944 - 45 som beskriver APR5
och dess förmåga att arbeta upp till 10GHz.

Dessa dokument visar på
en praktisk möjlighet att använda den upp till 10GHz.

Inte enbart en teoretisk möjlighet.

    Dokumenten avhemligades 1947 och kommer från Harvard University - Radio Research Laboratory - som ursprungligen konstruerade APR5
    The Radio Research Laboratory (RRL) was established in 1942 to develop countermeasures to radar. These countermeasures were simultaneously under development at the Massachusetts Institute of Technology (MIT). First located at MIT , the RRL soon moved to Harvard where it was operated by the University during World War II under contract with the U.S. Office of Scientific Research and Development.
  Mimum detectable signal as a function of frequency and other characteristics of APR5a
  Sensitivity of the APR5a in waveguidee 3 to 5 cm
  A variable cut-off high-pass filter for use with APR5a
    Övriga APR5:
    Blanking of the APR5 search receiver
    Waveguide installation for APR5a