Not RCA, but the Lear set up in the attached pic looks very similar.  I had a story in ER a year or so back about getting a Lear UT6A on the air, and it is still working fine.  Runs on 28VDC and puts out about 35 watts.  Mine is 4 channels, auto channel select with 4 preset grid and tank capacitors for max output from 3 to 7 mhz.  The original UT6 had 6 channels, and two had to be within so many percent of two others as they shared grid and tank caps.  This UT6A apparently went to some form of rework or modification center, as the changes made to it for only 4 channels were very clean and professionally done, and the nameplate was stamped with an additional 'A' after the original UT6 stamping.  Took quite a while to get info about this gear as just as I was needing info, and there was none on the internet, the Lear organization had just sent all their documentation about  Bill Lear's work to the Museum of Flight in Seattle, WA, and it was all still in boxes, a lot of boxes.    Then  along came the Covid restriction idiocy and made the task take more than a year.

Charlie, W4MEC in NC