MMDer Bob Fine wants to add MIDI control to his 30-note Unaphone
and he wonders if anyone is interested in this sort of project.  The
30 notes of Bob's instrument begin at "G" above Middle C and extend up
to "C" 2-1/2 octaves higher.  It's believed to be of early manufacture
since the dual-coil striking mechanisms were manufactured by Faraday,
not by Deagan.

I asked Mike Ames and Ron Perry (MIDIator Systems & Octet) if the Octet
MIDI converter could control the high current demanded by the Unaphone:
the coil resistance measures 2.2 ohms when cold, so at 6 volts it draws
2.8 amperes, and at 12 volts (Heavens!) it draws 5.6 amperes.  That's
much, much more current than drawn by organ magnets and the solenoids
in modern solenoid pianos.  A chord of 10 notes draws more than 50 amps
from the power source!

Mike said that no power amplifier circuit cards are commercially
available for this sort of high-current Unaphone application, so I'm
proceeding with the design of a 16-channel driver circuit card that
I hope Ron Perry can produce.  Two magnet driver cards will be used
in the 30-note Unaphone, three cards could operate the bigger models.

The circuit cards will accept the ribbon cable from the Octet UM0
MIDI converter and will control the 2.2-ohm Unaphone magnets in either
reiterating mode or single strike mode while the instrument is powered
by a 6- or 12-volt automobile storage battery.

But Ron needs more than one customer so that printed circuit card
production is economical.  Is anyone else interested in controlling
a Unaphone with MIDI wireline data?  Contact me for more information.

Robbie Rhodes
Etiwanda, CA