The Opus Challenger 3-in-1 combines a 5.25 inch double sided 40/80 track disk drive, a double density disc interface and a fast solid state RAM disc in a single unit, much the same size as a double disk drive unit. With 256k built-in RAM, which can be expanded up to 512k, plus the double sided, double density 80 track drive, the Challenger can upgrade the memory capacity of your BBC Micro to 1MB.

Unusually the Challenger does not connect to the BBC's floppy drive port but connects to the 1MHz bus and includes a pass through socket so devices can be daisy chained. The Challenger has a WD1770 disc controller.

The pictures show:

1. The front of the Challenger case
2. The Challenger circuit board with 256K RAM in the right middle and sockets for another 256K below. The WD1770 is above the RAM. The floppy disc drive connector is on the right edge and there is a connector for a second drive (?) next to it. The 1MHz bus cable goes under the circuit board and connects to the left edge with a connector for a pass through cable behind it.
3. The back of the case showing the ribbon connector to the 1MHz bus and the 4 wire power cable which plugs into the power socket underneath the BBC Micro.
4. The Challenger with the case removed showing the floppy disc drive with, just visible, the circuit board beneath it. The floppy disc drive is a Mitsubishi M4853-342MG.