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"ESTRADIN-230 — FANTASTIC VERY RARE VINTAGE SOVIET ANALOG MONOPHONIC SYNTHESIZER. A REAL MONSTER SYNTH WITH ENGLISH KNOBS AND PANELS.
ESTRADIN-230 is a Soviet Minimoog equivalent.
If you are familiar with Soviet synths you might know that ESTRADIN-230 has absolutely identical schematics (all 6 PCBs) with ALTAIR-231.


— OSC 1,2,3 registers - 2", 4", 8", 16", 32", LF
— OSC 1,2,3 waveshape select - triangle, saw, square, pulse, sine
— OSC frequency
— freq 1..3, freq 2, freq 3
— linked to keyboard pitch on/off (OSC 3 ONLY as MAIN OSC)
MIXER:
— OSC 1,2,3 on/off, level
— ext input level, on/off
— noise generator level, on/off
— noise mode switch: white/pink

— portamento on/off, rate;
— mod mixer knob: balance between modulated by OSC3 and noise, depth amount;
— pitch wheel (glissando)
FILTER:
— mod on/off
— cutoff, resonance, brightness
— attack, decay, sustain
— keytrack on/off

— attack, decay, sustain
— key hold memory on/off
— global section: main volume, phones volume, phones, A-440Hz tone on/off, power.
Connections: input, output, pedal input, phones.
Power supply: 220V/50Hz, 127V; fuze 0,125A
— Dimensions (mm) 754x466x110 (29.6"x18.3"x4.3")
— Weight: 18 kg (39.68 pounds)"