Concern with title
Hello. I will be serving as the advocate for this proposal. I'll shortly be providing some detailed comments, but let me now just say that I've never, to my knowledge, seen the phrase "three-coordinate" used in the radar literature in English. Wouldn't it be better to simply say "parabolic reflector [or "parabolic antenna"] pulsed radar", since it is the parabolic antenna that provides two coordinates.
Hi, Misha. Thank you for your comment. I have been looking through the radar-history books in English (Brown, Watson, and others) and I agree: the term "three-coordinate radar" is not used there although they of course mention and discuss the ways of determining the range, the bearing, and the elevation angle, i.e. the three coordinates. Moreover, this term is absent in the cited by me Russian-language book of Gen. Lobanov, who only had emphasized several times that, unlike other USSR experimental radars of that time, Zenit could determine all three coordinates of a target. Therefore I agree with your suggestion: let it be "Zenit parabolic reflector L-band pulsed radar, 1938."