This is an expander module that can be used in combination with A-138a or A-138b to expand the number of inputs by 5, i.e. 9 (or even 14) inputs altogether. It is a very simple module and is made only of 5 sockets, 5 potentiometers with knobs and 5 resistors. It was planned originally as a DIY project only, but due to some initial enquiries it was decided to manufacture this module in a basic form.
Due to the symmetry of the sockets and potentiometers two front panel alignments are possible that differ only in the printing. The picture shows both types. The left version has the same positions of sockets and knobs as the A-138a/b, for the right version the positions of sockets and knobs have been exchanged.
As neither design was preferred, both versions were offered, but only with a plain panel (no legend on panel) as the front panel silk-screen is one of the most expensive components for such a simple module - especially in small quantities.
Due to lack on constant demand fopr this module, it has been discontinued.
