> If I press the manual clock button the first or last step controls work.
> My problem is that it won't advance using a clock signal.

Does the LED of the internal clock oscillator of the A-154 display a clock
signal. Try this settings: clock ~ 7, PW ~ 5, with first stop control = 0,
last step control = 10, mode = 0 (forward). And pay attention to the correct
position of the master switch (right position).

And if you give back the control to the A-155 (master switch = left
position): does the A-155 work like before

Best wishes
Dieter Doepfer