Early Master Series
Econet Interface
This is the first type of Econet interface for the BBC Master and later machines.
It is branded "B ECONET", a reference not to the BBC Model B but perhaps to "Project B", the development name for the Master series.
As with the System and Atom Econet cards, and in a departure from the Master prototype, there is again no DIN socket on the board but instead a row of 5 pins which plug into the Master (or Archimedes or FileStore) motherboard providing a direct electrical connection to the DIN sockets on those machines.
There is no collision detect circuitry on this board, hence it is relatively sparsely populated. This led to problems and the later interface was soon introduced.