[Premium-Rx] Singer-Stoddart 533R-1 R-2 Receivers

[Doxemf]

Hello,Some time ago I picked up the Singer, (Stoddart) 533R-1 (1.5 to 10Mhz) and 533R-2 10Mhz to 100Mhz receivers. The 2 of 3 receivers along with the sweeper that are part of the 533 set   With the 3 receivers connected to the sweep generator interface then to an XY display the set becomes a limited function 1.5 mhz to 1 ghz spectrum analyzer.   The R-1 works fine and has an approx. 6.07mhz IF out. I have not checked the R-2 receiver. The VCO sweep unit does work but needs a going over and calibration.   These are marked Tempest Lab. Other than a brief reference on the Stoddart Radio Company history covering the R-3 UHF receiver, I have been unable to find anything else.Any help with manuals or other reference would be greatly appreciated.
Thanks,Bill Courtright