BTX Adapter for Expansion Port of Schneider Joyce (aka Amstrad PCW Expansion Port). From german company Wiedmann, though the PCB seems to be made by Dobbertin.
The device won't fit to the CPC6128 expansion port (which has different pin-outs as than Joyce) (and for the CPC6128, the connector would need to be mounted top-down).
Although case and PCB are marked "BTX", the chipset looks more like that of a RS232 interface, so it's probably only part of a BTX interface, and additionally requires an external BTX modem.
- Type: PC/HC Adapter
- Country: Germany
- Protocol: CEPT
- Year: 6-1989
- ID Number: 20110
- See also - http://btxmuseum.de/Hardware/ (german)