[Arran]

By the way, if you have a power supply for a Radiola 17 do not run it without a load on the B+ supply, there was an oversight in the original design where the B+ would surge without a load and damage the input filter cap, something they corrected with the Radiola 18, as was mentioned the transformers are the same but the circuitry was changed. Both Radiola's 17 and 18 were engineered and built by General Electric for RCA, which may explain why there were Victor and Brunswick versions. In Canada Victor used whatever radio chassis they could get prior to the RCA buyout, so you see Victors with Northern Electric chassis, or American Bosch chassis, (the Bosch was really a Radiola circuit, built under license, with a different chassis layout), prior to the "Microsychronous" models of the 1929 model year.
Regards
Arran