• Country
• United States of America (USA)

• Manufacturer / Brand
• DeForest Radio Telephone & Telegraph Co. (De Forest); New York

• Year
• 1921

• Category
• Commercial Transmitter (TX not Transceiver)

• Radiomuseum.org ID
• 201519

• • alternative name: Lee De Forest Mfg.

• Main principle
• Transmitter

• Power type and voltage
• Batteries / addl. power jack

• Loudspeaker
• - - No sound reproduction output.

• Material
• Wooden case

• from Radiomuseum.org
• Model: Radiophone Transmitter OT-25 - DeForest Radio Telephone &

• Shape
• Tablemodel, Box - most often with Lid (NOT slant panel).

• Dimensions (WHD)
• 13 x 11.25 x 8 inch / 330 x 286 x 203 mm

• Notes
• The De Forest OT-25 Radiophone Transmitter had a reliable range of up to 60 miles. To supply the plates with a potential of 350 or 500 volts, a 32 or 110 volt dynamotor or a 32 or 110Volt motor-generator is required while, for the filaments and microphone, a 10 volt storage battery is required.

• Net weight (2.2 lb = 1 kg)
• 35 lb (35 lb 0 oz) / 15.890 kg

• Literature/Schematics (1)
• Deforest Radio Equipment Catalog H page 16

• Author
• Model page created by Alan Larsen. See "Data change" for further contributors.

• Other Models

• Here you find 158 models, 133 with images and 16 with schematics for wireless sets etc. In French: TSF for Télégraphie sans fil.
  All listed radios etc. from DeForest Radio Telephone & Telegraph Co. (De Forest); New York