Thanks. I'm pretty confident that the google-earth image is a KS-1 SAM battery on the testing range.
But I have a much greater mystery. Nosing around Dingxin looking for SAM batteries, I've found a Russian made P-37 "Bar Lock" radar:
It's distinctive tandam array make it a pretty reliable ID.
Bar Lock is quite an old radar and normally associated with the SA-5 Gammon long range SAM, which China doesn't have. at any rrate all the usual SA-5 stuff is not at this site so no suggestion China has SA-5. But it is a long wavelength system of the sort generally associated with detecting Stealth aircraft. Is this part of China's anti-stealth research?