Lotus SG4 Portable Valve Radio Lotus SG4 Portable Valve Radio Product Leaflet Two leaflets, both double sided, giving details of the Lotus SG4 transportable radio receiver. Click the thumbnails to enlarge. 585kb – Lotus SG4 valve radio 690kb – Lotus SG4 valve radio 340kb – Lotus SG4 valve radio 380kb – Lotus SG4 valve radio