homemade polysynth

a quixotic attempt to build a hybrid analog polyphonic synthesizer (and fix some of the ones I already have)

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Replacement Roland System 100 Model 101/102 power supply.

https://github.com/minisystem/System-100-PS22-PS24

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Oberheim SEM pot repair

Just brought an early Oberheim SEM back to life. The pot that sweeps the filter type had failed and upon disassembly it was apparent the resistive track had completely disintegrated. It has a built-in switch for bandpass mode, so finding a replacement seemed impossible. I took a tip from this site and found a CTS donor pot. The phenolic board with the resistive track mounted on it is the same shape as the original one so it can be swapped.  I couldn't easily obtain the PCB pin type but was able to improvise with the solder lug version, which is readily available from Digikey (ignore the Digikey photo, it incorrectly shows the switch version). 

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About as tidy as it gets.

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Panel design nearing completion. #eurorack #tr808 #808 #drummachine #inkscape #opensource

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Playing well together. #korg #sq1 #sdd3000 #delay #roland #system500 #eurorack #tr808 #808

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Eurorack TR-808 gets a sequencer

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MIDI sequencing of Eurorack TR-808 clone. Toms and Congas and Rim Shot/Claves switched electronically, allowing dynamic assignment in the same sequence.

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MIDI sequencing enabled. #eurorack #808 #tr808 #drummachine #congas

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Snare secrets revealed. #volcabeats #korgvolca #volca

http://system79.com/korg_volca_beats_snare.html

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TR-808 Start/Stop button replacement with new Cherry MX switch assembly. #tr808 #cherrymx #3dprinting

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Makes noise. Analog voice card test bed. #eurorack

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DDR3 240 DIMM format analog voice card in test bed. 2VCO, VCF, VCA, 2ADSR. #polysynth #synth #analog

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Software to hardware. #kicad

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Polysynth voice card oscillator FM test. #polysynth #eurorack #synth #analog #sq1 #korg

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Starting work on new module inspired by a classic but -ring mod, +slew #eurorack #system100m #lfo

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First 3D view of main board and step switch board assembly. #eurorack #tr808 #kicad #freecad #drummachine