[R-390] Manual Help Needed

[John Heck]

Folks,
  I picked up a very nice HP low frequency signal generator at Dayton a few years ago. It is actually bigger and heavier that an R-390A! It is very clean, complete with all accessories, and looks hardly used. It is a TS-535 A/U, all tube. I have had it on my counter all afternoon and it is very stable on all bands, and still in fine alignment. I have looked everywhere I know to look for a manual, including Agilant's site, but no luck. Can anyone point me in the direction of a manual for this instrument? Thanks very much!
  John, KC8ETS