• Country
• People's Republic of China

• Manufacturer / Brand
• Tianjin 天津渤海无线电厂 Tianjin Bohai Radio Factory; Tianjin (N)

• Year
• 1968 ??

• Category
• Broadcast Receiver - or past WW2 Tuner

• Radiomuseum.org ID
• 178105

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

• Number of Transistors
• 7

• Semiconductors
• 3AG51C 3AG51C 3AG51C 3AX31A 3AX31A 3AX31B 3AX31B 2CP10 2AP9 2AP9

• Main principle
• Superheterodyne (common); ZF/IF 465 kHz; 3 AF stage(s)

• Tuned circuits
• 5 AM circuit(s)

• Wave bands
• Broadcast only (MW).

• Power type and voltage
• Dry Batteries / 1.5 Volt

• Loudspeaker
• Permanent or electro-dynamic (moving coil), system not known yet.

• Material
• Plastics (no bakelite or catalin)

• from Radiomuseum.org
• Model: Seagull 海鸥 709 - Tianjin 天津渤海无线电厂

• Shape
• Very small Portable or Pocket-Set (Handheld) < 8 inch.

• Dimensions (WHD)
• 87 x 88 x 42 mm / 3.4 x 3.5 x 1.7 inch

• Notes
• The radio model Seagull 海鸥 709 (Haiou) has the following key features 主要性能: Frequency range 频率范围: broadcast band 525 - 1605 kc. Sensitivity 灵敏度: < 1 mV/m. Selectivity 选择性: > 14 dB S/N. Set audio output 额定功率: 50 mW. The IF is 465 kc. Loudspeaker impedance is 8 ohm. 3 diodes. See also the similar models Seagull 海鸥 709-1 and Seagull 海鸥 709-2.

• Mentioned in
• 03-Transistor Radio Circuit Manual 1981 August (1 of 5) (page 239.)

• Literature/Schematics (1)
• 02-Radio Manual unknown date, 380 pages (page 87, drawing 263.)

• Author
• Model page created by Ernst Erb. See "Data change" for further contributors.

• Other Models

• Here you find 25 models, 16 with images and 23 with schematics for wireless sets etc. In French: TSF for Télégraphie sans fil.
  All listed radios etc. from Tianjin 天津渤海无线电厂 Tianjin Bohai Radio Factory; Tianjin (N)