Technosaurus Microcon II SN 2218

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"Just serviced, all pots and jacks cleaned. Power supply 220V included.
The top panel starts (from left to right) with the control section. Here you'll find a dial to adjust the Glide rate, another for tuning, and a little red trigger button so you can hear the sound.

The VCO section begins with the analogue oscillator. This can be switched between square and saw shapes, while another switch drops it up and down by two octaves. The raw sound is reinforced with a sub oscillator set to a square. A mix control sets the levels between them, while the pitch can be modulated via the LFO.

Microcon offers square and triangle shapes - on a switch, naturally - and a dial to set the speed. The two-page manual doesn't list the speed range, but it goes from around eight secs at the slow end, to fast enough to produce some nice buzzing, metallic FM tones.

Sandwiched in the middle of the box is the ENV section. This is the only envelope onboard, so this means the VCA and the Filter have to share it.

The VCF section features a switchable 12dB/24dB low-pass filter with resonance control. The 12dB filter has a slightly brighter, buzzier, grungier tone to it that provides a nice contrast to the regular 24dB sound.

Mod sources include the LFO, ENV and CV, which switches on key-tracking for the cutoff point. The Mod wheel can also be used to control the cutoff point over MIDI, and can be used over three-quarter of the filter's full range.

You can use it as a MIDI to CV/Gate converter as well, as there are two more sockets on the side: these are both balanced mini-jacks and work the same way, with each one carrying two separate signals. The first outputs CV1 and CV2 to patch into another analogue synth or module. CV1 is the on the tip, and outputs the VCO pitch, while CV2 is on the ring, and is linked to the modulation wheel, aka MIDI CC1. The second mini-jack socket fires out the Gate signal on the tip, and the ring is used as an input to mute the OSC. This might seem odd, but it's necessary if you fancy using the VCF input as there is no other way to take it out of the mix otherwise"