marconi: V2A (V-2-A); Marconiphone

"Spade tuning" = Eddy-current tuning. Also applied in the "Crystal A" set, where the loss cannot be compensated by reaction...

 Spades (coils removed)

 Left hand spade 

  range coil

 tuning rod with "scale" markings
 
There was also a "Micrometer tuning device" available, an attachment which can easily be made and permits of very fine adjustment of the tuning rods.

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