• Country
• United States of America (USA)

• Manufacturer / Brand
• Hammarlund Mfg. Co. Inc.; New York, NY

• Year
• 1948 ??

• Category
• Amateur Transmitter (only)

• Radiomuseum.org ID
• 110755

• Number of Tubes
• 6

• Valves / Tubes
• 807 7C5 7C5 7C5 7C5 5U4G

• Main principle
• Radio Frequency Amplification only

• Wave bands
• Short Wave (SW only)

• Power type and voltage
• Alternating Current supply (AC) / 105-120 Volt

• Loudspeaker
• - - No sound reproduction output.

• Material
• Metal case

• from Radiomuseum.org
• Model: Transmitter Four-20 - Hammarlund Mfg. Co. Inc.; New

• Shape
• Tablemodel, low profile (big size).

• Dimensions (WHD)
• 15.25 x 8.25 x 9.5 inch / 387 x 210 x 241 mm

• Notes
• Crystal controlled CW transmitter for 80,40, 20 and 10 m-band. Final stage uses plug-in coils. 20 watts output. AM with available "Four-11" modulator unit possible. Price is 1948 including coil for 10 m.

• Net weight (2.2 lb = 1 kg)
• 31 lb (31 lb 0 oz) / 14.074 kg

• Price in first year of sale
• 120.00 $

• Source of data
• -- Original-techn. papers.

• Literature/Schematics (1)
• ARRL 1948, Catalog section, page 45

• Author
• Model page created by Otto Frosinn. See "Data change" for further contributors.

• Other Models

• Here you find 144 models, 92 with images and 58 with schematics for wireless sets etc. In French: TSF for Télégraphie sans fil.
  All listed radios etc. from Hammarlund Mfg. Co. Inc.; New York, NY