Grundig SSB Zusatz SSB Unit Rare accessoire for Grundig Satellit receivers The Grundig Satellit radios are great for Short Wave listening, but cannot receive SSB transmissions natively. From 1969 to 1979 these units were produced, containing the BFO, Gain control, and Noise limiting circuitry. My unit comes with a metal strip with a screw;. In the bottom of the radio, there is a special hole for fixing this strip, and then the SSB unit slides on it easily. The unit is the Zusatz 2000, produced for the Satellit 2000 and 2100. Apparently, the radios come with two different Intermediate Frequencies, namely 460kHz for most of Europe, and 452kHz for the Benelux (besides the first IF, 2000kHz). The Beat Freuency of the unit must match the second IF of the radio. It can be retuned, but I do not know if the alignment range is large enough to change between 452 and 460 kHz without electrical modification.