Links

Grundig
Grundig Radio Boy (en) (1863 Hits) (Lots of information about Grundig world receivers)
Grundig Satellit Warehouse (en) (2708 Hits) (Manuals and Schematics for Grundig Satellit radios)

Other receivers
Nostalgische Radios (de) (1921 Hits) (Very nice page about tube- and transistor radios with lots of images, descriptions, circuit diagrams and other documents.)
RadioMuseum.org (de) (en) (1675 Hits) (Very large site about vintage radios)
Technisat/Sangean ATS909 Kurzwellenempfänger (de) (1905 Hits) (Information about the ATS909)

Tests and articles of receivers
Martin's Radio Pages (de) (1823 Hits) (Lots of top quality tests about shortwave receivers.)
Modern Shortwave Receiver Survey (en) (1947 Hits) (One of the most extensive receivers lists online)
Radio Netherlands Receiver Survey (en) (1366 Hits) (Tests of all current and some discontinued world receivers)
Welchen Empfänger brauchen Sie? (en) (1458 Hits) (Tips about sw receivers from the team of the HJCB Quite, the Voice of the Andes)