> I'm having problems with my Doepfer A155 sequencer. I use it with the
> A154. My problem is in the A155 first CV sequence row. Only two steps
> of the eight actually produce voltages. I'm not sure why this is, as
> the second CV sequence works wonderfully.

Sounds like trouble with the ribbon cable connecting everything
together. Each step in the sequence is 'addressed' via this cable,
using 3 binary lines (hence 2 x 2 x 2 = 8) - as you are only getting
two steps from the top row, it sounds as though the ribbon is only
making connection on 1 of the 3 address lines. The ribbon goes to the
bottom board (second row), middle board (top row), and then to the
trigger/gate board. Since the bottom row is working, the signal appears
to be good there, so there may be a break in the cable, or the
connector to the top row (middle board) is bad - are the trigger/gates
working properly (which are on the end of the ribbon)

What you could try is to place the connector for the bottom
board/second row onto the middle board/top row, but take care to keep
the orientation the same - just leave the bottom board unconnected, and
see if this makes the first row work. If so, you'll need a new ribbon,
as it is not worth trying to fix a bad one.

Also if the ICs are in sockets, check these are seated properly,
especially the '4051 which controls the switching.

Tim