Regarding Bernt Damm's question about the Aeolian transposing
tracker bar and the 8-note switch, I owned a half-Duo-Art Steck
that I restored some time ago and that unit had the (fairly bulky)
transposing mechanism.  It also had two switch pouches to cut off
notes 1-4 and 84-88 to allow the Duo-Art system to function.

Only the Accompaniment was controlled by the Duo-Art, but notes 84-88
needed to be cut off in order to play Duo-Art rolls successfully.  The
Themodist [mode] came into play only if the Duo-Art switch was pointed
to the arrow in the centre on the switch panel in the spool box.  To my
recollection, this system did not work properly if the tracker bar was
transposed away from true centre.

If there are no rectangular (and rather thin) 8-nipple pouch blocks at
either side of the spool box, then they are likely missing -- not an
unusual occurrence in Sydney, where technicians of bygone days seemed
to delight in disconnecting or removing almost all expression devices
even in the best players.

Regards,
Paul Brennan
Sydney