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" from my uncle's garage. never see light about 30 years
The Synthesizer 101 section is a fully self-contained analog mono-synth. It features a 37-note keyboard (with no performance controls, velocity or aftertouch), and lots of sliders to tweak. Its design is similar to the SH-series analog synths. Controls for the VCO, LFO, VCF lowpass/highpass filters, VCA with ADSR, Noise, and Portamento/Glide effects are all within hands reach. There's also a handy A-440Hz tuning oscillator
The Expander 102
its keyboard-less version of the 101, designed to stand upright and behind the main Synthesizer 101.The Expander is identical to the Synthesizer except that it replaces Portamento/Glide effects with a Sample-and-Hold feature for the LFO, the Noise gen. is replaced by a Ring Modulator, and the A-440 tuning osc. is replaced by weak/strong sync inputs and a mix-in jack. The Expander is an excellent way to add more oscillators and synth effects (the s&h and ring-mod) to a System 100. The oscillators can be synced if you have both modules. The 101 & 102 are already internally patched and ready to produce sounds, but that can be bypassed by external patching.
Sequencer 104.
This analog sequencer can be used to drive your System with a 12x2 step pattern sequencer. It features variable gate time, series or parallel modes, Start, Stop, Continue, and Step buttons."