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glide fix

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George Dorn 2024-07-28 11:40:21 -07:00
parent aac0a4a5b4
commit a5c5ff12ce
1 changed files with 30 additions and 44 deletions
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Schematics/schematic_bugs_v1.md
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@ -1,57 +1,43 @@
Assembly notes:
WARNING: There is a connection on the v1 board between R25 and R1, probably a result of KiCad adding junctions during a component move. This needs to be
severed. [See this
image of the bad trace](bad_trace_v1.jpeg).
Two show-stopping bugs:
- Errant connection between R25 and R1. This needs to be severed. [See this image of the bad trace](bad_trace_v1.jpeg).
- Wrong side of the glide capacitor (C13) is connected to the integrator Op-Amp (U3-10). Cut the current trace and bodge from the other leg of the capacitor.
Assembly Notes:
- Do not connect the Normal pin for Pause (J19/J18); the schematic is incorrect
- the current 12-position rotary switches are actually 2p6t, which means only six different step counts are available until the replacement arrives
- Wiring SW15 (once/stop) and cascade out is easier done via skywiring; only one cross-board wire is needed, vs 3 if the PCB is used.
- the current 12-position rotary switches are actually 2p6t, which means only six different step counts are available until the replacement arrives
- LEDs go in long leg down (from the front)
- Clock POT is too small; need more than 100k to get below 200bpm
Schematic notes:
- C1 is too small for a 1uF capacitor. 1uF may be unnecessary, though.
Schematic fixes:
- C1 is too small for a 1uF capacitor; expand a bit, but also size it for a box film cap instead of the 600v monsters we've been using
- C3 and C4 could use larger spacing
- C7 is a ceramic 104 power cap like C5, C6, C8, C9, C11, C12; space accordingly
- C10, C14 too small for film; is film needed?
- Fix R25/R1 connection
- One socket connection is on the wrong side of the board, adding an extra cross-board wire that shouldn't be so hard.
- In general, try to avoid putting any UX connections on the larger board underneath the smaller board.
Try:
- C1: enlarge footprint; a box film cap for 100v is smaller, but not that small
- C3 and C4 could use slightly larger spacing on the thru-holes.
- C7 is a ceramic 104 power cap like C5, C6, C8, C9, C11, C12.
- Move any UX connections on the lower board out from under the smaller board, for convenience
- C10, C14 is a guessed value; could be other values, ceramic may work, test debouncing. Maybe enlarge footprint if needed.
- Resistor footprint could stand to be +1mm between legs
-- Don't put R8 so close to R26
-- D36/R47 too close
- Trim 5mm from vertical for both panels, to make fitting inside a case easier. Or 10mm if it can fit; losing the bodge area.
- Don't put R8 so close to R26
- D36/R47 too close
Testing before powering up:
~Ins:
Clock In - diode to U2-3
Clock In Normal - 1k to U2-8 (AND NOT short to U2-10)
Clock Rate - variable resist +6k between U2-8 and U2-9
Reset Sw - when pressed, short +12V and Reset In socket
Reset Socket to U3-3 = capacitor measurement roughly 15nF (has a resistor as well)
Once/Cont When in Cont mode shorts Casc Out normal to Reset In
Pause CV In - U1-13 (can get at from top when assembled)
Stop Switch - 10 ohms between U1-14 and U2-1 when off, more like 1M ohms when off
Single Step - 12V through 10k Ohms to U-1-14, more like 1M when off
Glide In - ~27K to U3-8? No, transistors maybe activate?
Assembly Tests:
Ins:
- Clock In - diode to U2-3
- Clock In Normal - 1k to U2-8 (AND NOT short to U2-10)
- Clock Rate - variable resist +6k between U2-8 and U2-9
- Reset Sw - when pressed, short +12V and Reset In socket
- Reset Socket to U3-3 = capacitor measurement roughly 15nF (has a resistor as well)
- Once/Cont When in Cont mode shorts Casc Out normal to Reset In
- Pause CV In - U1-13 (can get at from top when assembled)
- Stop Switch - 10 ohms between U1-14 and U2-1 when off, more like 1M ohms when off
- Single Step - 12V through 10k Ohms to U-1-14, more like 1M when off
- Glide In - ~27K to U3-8? No, transistors maybe activate?
Outs:
Clock Out - 1K to TP5
Gate Out - 1K to U2-14
Case Out - Diode from rotary pin 13?
CV Out - 1K to U3-7
Debugging issues:
Glide section not working right, just pegging the output to +10V?
Clock POT is too small; need more than 100k to get below 200bpm~
- Clock Out - 1K to TP5
- Gate Out - 1K to U2-14
- Casc Out - Diode from rotary pin 13
- CV Out - 1K to U3-7