Not familar with the radio but know about Arcturus 28 tubes. They were one of the first AC tubes with a carbon rod filament and operate on 15 volts. Since 5 pin bases weren't available cathode and filament are both connected to pin #1. Most likely tubes are blue glass. Others in your radio may also be 15 volt AC tubes?
Be careful with these rare tubes. Carbon filaments break easily if dropped.
Radio would have been made in late 1927 or 1928.
Norm
:hello: I recently bought an interesting old radio.I have not found any information on it.The name on it is Ulectra.The tag reads Utah Electric Radio Co. Salt Lake City Utah.The set is on four legs,the top lifts which shows six dark blue arcturus 28 four prong tubes and three othertubes.Any information would be appreciated.
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