The "New Gem"

 The part chassis of a "plug in" coil wireless was spotted  at a dealers - interest aroused -  but then it turned out to be a customer's property and not for sale.These "plug in " coils first appeared in 1922.

None the less, interest had been aroused, but there was little chance of finding another original set like it, so a different approach was tried..........

From a mid 1920`s copy of "Brown Bros Radio receiving sets and components" a likely set was chosen- an Edison Bell "GEM".

Philip Knighton`s shop in Wellington was raided for suitable components--what could be accomplished was constrained by what was available. The result is the "New Gem" which bears a fair resemblance to the original.


A particular feature was that the valve holder pin sockets were moulded directly into the base panel (courtesy of some Araldite). Loudspeaker results were remarkably good particularly so after a friend pointed out that the tuning capacitor lead had been inadvertently connected to the wrong side of the detector grid capacitor.The swinging coil reaction operated differently from the original in being a "rotary swing," whilst the original was a "sliding swing" A filament rheostat was included, though a bit superfluous with a stabilised 2 volt supply. It was surprising how crudely made the rheostat was - real cottage industry.

The tuning condenser is unusual in that it gives continuous 360 degrees rotation. The frame of the condenser is joined to it`s fixed vanes, the moving vanes being the `live` ones. The moving vanes are semi-circular and follow a linear law

The intervalve transformer had to be turned on it`s side to get a reasonable cabinet height


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