Many thanks to SWLing Post contributor, Dan Robinson, who shares this YouTube video comparing four of his receivers: the McKay Dymek DR33-C6, the East German made RFT EKD 515, Japan Radio Company NRD-301A, and his Watkins Johnson 8718A/MFPWJ WJ .
The Watkins-Johnson HF-1000 (and NSA version, WJ-8711) are mentioned in this article
On January 11, 2012 the National Security Agency (NSA) released a pre-1995 article entitled “Receiver Dynamics” from its classified internal magazine, Cryptologic Quarterly. It contains an excellent, well-written explanation of the specifications of shortwave receivers used by some of NSA’s K4 divisions.
Download the article here (PDF).
Thanks to Ed in the SWLfest list for the tip!