A long time ago I found a schematic online that used a 5842 DC coupled to a series fed 45. It used a 0D3 voltage regulator tube to set the 45's bias and provide the plate voltage for the 5842. IIRC it used either LEDs or batteries to bias the 5842. I breadboarded it at the time but experienced noise problems and gave up on it, it was probably the lack of gridstoppers on the 5842 that was responsible. I thought it might have been in a back issue of Valve but I can't seem to find it in the archives. If anyone can steer me in the right direction I'd really appreciate it.
Regards
Robert Lees