Brand and type: Halson. Fellow collector Scott Robinson thinks this is a model 20A. He kindly sent me the schematic.
Produced: New York, according to another US collector, estimated 1935.
Cabinet: Several kinds of wood. It never had a back I suppose.
Tubes: 25Z5 (full wave rectifier) - 43 (output pentode) - 77-78-78, all pentodes. This is definitely not a super. All tubes are from ADZAM. Is there a link between ADZAM and MAZDA? I have tubes of that manufacturer too.
Power: only 220 V AC, a bit odd for a US radio.
Obtained: in 1987 at a swap meeting.
Condition: 7 . There's a little hole in the celluloid dial behind which the lamp is visible.
Working: good, it covers only the medium wave. I had to replace the dead output transformer. There's no mains transformer, the dial lamp is also the fuse. Triple tuning cap. One of the knobs is for bandspread, it cuts the MW into 2 parts. For lack of a back, the mains connected directly to the chassis and metal maiden screws in the knobs, I regard this as a dangerous device. One should only play it when connected through an additional isolation transformer.