The 1926/7 Graves "Vulcan"

 

And it`s advertisment in the Wireless World of January 26th.1927 :-

A two valve set, interesting in that it was intended to allow the less affluent to "trade up" from using a crystal set with earphones to one which provided loudspeaker reception. This it does admirably; but now mostly tuned to Radio 4 rather than 2LO.

 

 The Wireless World review of 27th. July 1927,when apparently from it`s paragraph 1, the BBC thought listeners were happy at being restricted to Crystal sets !

 

 There was a lot provided for 10/6d down (52.5p)

including :-

Aerial wire, rope halyard, wire, pulleys, porcelain insulators, lead-in tube, earth clip, and batteries.

 

 

 

The simple internals of the original set. The flashlamp battery used for grid bias is still available today.Only the flexible leads to the set and to the swinging coil reaction needed replacing.

 

 

 The circuit diagram.

The reaction coil actually swings across the two tuning coils through 180 degrees and requires to be reversed as the coils are switched from short to long.

The positioning of the .001uF condenser seems rather odd.

 

 Operation of the swinging coil reaction.

 Where possible the wiring has been run under the baseboard.

 

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