The signal has 2 independent semaphores and an open gray lattice mast. The signal changes from red (Hp 0) to green (Hp 1) or red (Hp 0) to green/yellow (Hp 2).
- Digital decoder with additional, digitally controlled functions (f1, f2, f3 or f4) when operated with the 6021 Control Unit. The functions present depend on how the locomotive is equipped. Standard function (function) active during conventional operation.
- Digital decoder with up to 32 digitally controlled functions. The quantity depends on the controller being used.
- DCC decoder
- Era 3
- Era 4