1920s Ferranti AF5 Large Audio Frequency Transformer

This small 1920s Ferranti AF5 Large Audio Frequency Transformer is really a work of art. It's never been out of its box and is excellent condition.

The impedance has been measured as follows:

• Primary: 2K4
• Secondary: 30K8

The box is scuffed and discoloured and one of the flaps is missing and another has detached.

A copy of the original specification is shown below:

• Approximate Size (WHD): 7.8 x 9.5 x 7 cm
• Ratio 1 to 3.5
  
• Inductance 120/170 Henries
  

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