• Country
• Czechoslovakia

• Manufacturer / Brand
• KNN, Praha

• Year
• 1927 ??

• Category
• Broadcast Receiver - or past WW2 Tuner

• Radiomuseum.org ID
• 167791

• Number of Tubes
• 1

• Valves / Tubes

• Main principle
• TRF with regeneration

• Wave bands
• Broadcast (MW) and Long Wave.

• Power type and voltage
• Storage and/or dry batteries

• Loudspeaker
• - only for Earphone!

• Material
• Wooden case

• from Radiomuseum.org
• Model: Negadyn - KNN, Praha

• Shape
• Portable set > 8 inch (also usable without mains)

• Notes
• Negadyne is a certain high sensitive demodulating circuit using a space charge tetrode, where positive feedback acts through interaction between the grids, hence no reaction coil is necessary. Alternatively a second mode can be selected: Crystal detection with audio amplification.

• Author
• Model page created by Gabriel Toth. See "Data change" for further contributors.

• Other Models

• Here you find 42 models, 6 with images and 0 with schematics for wireless sets etc. In French: TSF for Télégraphie sans fil.
  All listed radios etc. from KNN, Praha