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Hi. Where in the synth are you actually scoping for your waveforms? You should have triangle, sawtooth and square waves. I’m not so sure that graphic on the front panel for sawtooth is correct. Doesn’t sound like your triangle is healthy. Can you read schematics? I linked to it if you don’t have it. You can see the test points to look with your scope and check waveforms. If any are clipped, I would start confirming my voltages, first at the power supply, then at the actual VCO 3 circuit. Offset or clipped waves usually indicate voltage problems, for whatever reason causing it. Are the electrolytic and tantalum caps original? If so, you need to change the caps and give it a good cleaning and calibration first.
You can see at the 10K Color pot the 3 incoming waveshapes before the color pot mixes them.
Schematic: http://manuals.fdiskc.com/flat/EML%20101%20Schematic%20Re-Draw%20%28%20Draft%201%20%29.pdf
Peter
From: emlsynth@yahoogroups.com [mailto:emlsynth@yahoogroups.com]
Sent: November 12, 2014 10:41 AM
To: emlsynth@yahoogroups.com
Subject: [emlsynth] Correct or Incorrect - EML 100 OSC 3 waves?
Was scoping my EML100's waves and I noticed the front panel for OSC 3 draws a Triangle, then what looks like a half rectified sine and then a square as the wave shapes. When scoped I see a Triangle with the bottom clipped instead of a triangle - sort of like a half rectified triangle but not on zero volts, then a Triangle/Square hybrid that is nothing like a half rectified sine in the center, then a square as expected on the right.
So… was just wondering if that's "normal" for the 100 and the panel is wrong, or am I having a problem with my wave shaping?
Nick