Tianjin Bohai Radio Factory; Tianjin (N) 天津渤海无线电厂:

Tiān​jīn​ 天津; Tianjin is a municipality in north China (N), abbr. 津. It used to be called Tientsin. As municipality it is directly under the central government, without being part of a province but its own government can be in a certain district, here it is Heping District 和平区.
Bó​hǎi (or Bó​ Hǎi​)​ 渤海 (wrong is 勃海 since the Han dynasty renamed it): Bohai is the Han dynasty province around the Bohai sea. The Bohai sea is between Liaoning and Shandong. There is a "Bohai Economic Circle", an economic region including Beijing, Tianjin, Hebei, Liaoning and Shandong.
无线电厂, trad. 無線電廠 (Radio Factory) = Wú​xiàn​diàn ​无线电 = Wireless (we call it Radio, because most used); Chǎng​ 厂 trad. 廠 = Factory (yard / depot / workhouse / works / (industrial).

Brands:
Gongnongbing, 工农兵 in Mandarin gōng​nóng​bīng​ trad. Chinese 工農兵 (Workers, peasants and soldiers), was also used by Shanghai No.2 Radio Factory.
Hai He 海河 (Haihe River)is a system of five waterways around Tianjin, flowing into Bohai 渤海 at Dagukou. Careful: Sometimes the same models with the same brands have also been made by the Tianjin Tanggu Dongfanghong Wireless Factory 天津塘沽东方红无 线 电 厂. An example is model BS-402.
Haiou 海鸥 (Seagull).

An example of an early transistor radio from the Tianjin Bohai Radio Factory is model Gongnongbing 工农兵 301. On page 118 of the Transistor Radio Manual 1983, we find model BS-501 made for two brands, 海河, Hai He, and 红波, Hongbo, but also by three manufacturers!