Trio 420U

• Country
• Czechoslovakia

• Manufacturer / Brand
• Tesla; Praha, Bratislava etc.

• Year
• 1956/1957

• Category
• Broadcast Receiver - or past WW2 Tuner

• Radiomuseum.org ID
• 30889

• • Brand: Supraphon

• Picture
• Schematics

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Click on the schematic thumbnail to request the schematic as a free document.

• Number of Tubes
• 5

• Valves / Tubes
• 12H31 12F31 12BC32 35L31 35Y31

• Main principle
• Superheterodyne (common); ZF/IF 468 kHz

• Tuned circuits
• 6 AM circuit(s)

• Wave bands
• Broadcast, Long Wave and Short Wave.

• Power type and voltage
• AC/DC-set / 120/220 Volt

• Loudspeaker
• Permanent Magnet Dynamic (PDyn) Loudspeaker (moving coil) / Ø 16 cm = 6.3 inch

• Power out
• 2 W (unknown quality)

• Material
• Bakelite case

• from Radiomuseum.org
• Model: Trio 420U - Tesla; Praha, Bratislava etc.

• Shape
• Tablemodel, with any shape - general.

• Dimensions (WHD)
• 320 x 215 x 175 mm / 12.6 x 8.5 x 6.9 inch

• Notes
• Variant 420U-2 has different tuning scale.

• Net weight (2.2 lb = 1 kg)
• 3.5 kg / 7 lb 11.3 oz (7.709 lb)

• Source of data
• -- Collector info (Sammler)

• Mentioned in
• Ceskoslovenske Rozhlasove a Televizni Prijimace I a II

• Other Models

• Here you find 1868 models, 1193 with images and 674 with schematics for wireless sets etc. In French: TSF for Télégraphie sans fil.
  All listed radios etc. from Tesla; Praha, Bratislava etc.