• Country
• United States of America (USA)

• Manufacturer / Brand
• Polytechnic Research & Development Co, Inc. (PRD); Brooklyn, NY

• Year
• 1944 ?

• Category
• Service- or Lab Equipment

• Radiomuseum.org ID
• 133382

• Wave bands
• - without

• Loudspeaker
• - - No sound reproduction output.

• Material
• Metal case

• from Radiomuseum.org
• Model: Precision Variable Attenuators - Polytechnic Research &

• Notes
• The PRD family of waveguide variable attenuators ranges fro 2 up to 40 GHz. Metallized glass attenuating element.
  

• Source of data
• -- Original prospect or advert

• Author
• Model page created by Emilio Ciardiello. See "Data change" for further contributors.

• Other Models

• Here you find 11 models, 2 with images and 0 with schematics for wireless sets etc. In French: TSF for Télégraphie sans fil.
  All listed radios etc. from Polytechnic Research & Development Co, Inc. (PRD); Brooklyn, NY