via
this auction

"Serial# 5599 Here are some details about the unit: The
Steiner Microcon is a complete synthesizer (less keybaord) in a single module.
It has its own power supply, VCO, LFO, VCF and envelope generator, thereby
combining all of the most needed parts of a synthesizer in one unit. "It can be
used with synthesizer accessories such as sequencers, electronic valve
instruments, guitar slave-drivers, pitch followers, or with a keyboard. Multiple
units can be combined with a guitar controller to form full polyphonic
synthesizers at a fraction of the cost normally expected. Combined with a
regular synthesizer, it ads an extra 'voice' to your present system.
'Oscillator stability and tracking are the best that state of the art will
allow. Numerous inputs and outputs are available on the front and top of the
unit. Other signals available inside can be brought out for special
applications, and connected to other equipment in a variety of useful ways. The
Microcon truly packs alot of synthesizer into a small space (which looks to be
about 4-inches by 6-inches. There are 8 knobs and 6 switches. The VCO has knobs
for course and fine tuning and switc hes allowing selection of "three
waveforms". The LFO has knobs for rate and level and a switch for beat and is
available for vibrato. The VCF has knobs for frequency and gain, as well as a
switch for resonance. The Envelop Generator has knobs for attack and decay, as
well as a switches to enable damp (a quick release decay) and sustain. The VCA
is described as a "trigger controlled audio gate". Connections include positive
and negative trigger out, VC filter in, calibrated and uncalibrated voltage
control ins, a signal out (which "can be paralleled"), and a trigger in.
According to the product literature the "beat function causes the VCO to sound
like to sound like two oscillators beating together.' The Minicon was rumored to
be used as the synthesizer innards of the Hagstrom Patch 2000 guitar
synthesizer."