Enclosure not stated · 2 knobs
Demeter Tremulator
Based on the Demeter Tremulator· 3 other boards clone it
- Category
- Tremolo
- Price
- see vendor
From the vendor
An optical tremolo. A dual op amp LFO (with zener diodes limiting its swing) drives an LED/LDR optocoupler through a buffer, and the optocoupler shunts the signal after a unity-gain op amp stage to vary the volume. The post says Jonny Greenwood used one and that the layout can also be built as a Fulltone Supa-Trem, which it calls a copy of the Tremulator with a few mods.
The layout notes say: leave out the hard/soft switch for a basic two-knob Tremulator, and add a 47u or 100u filter capacitor at the 9V jack for noise filtering. The layout can also be built as a Fulltone Supa-Trem.
Schematic
The schematic is in the post. Open it at Revolution Deux. No KiCad fragment has been drawn for this circuit yet.
Parts list 33 rows
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Check before you build · 4 values the reader of this schematic was not sure of
- The Speed pot is drawn as 1k; the layout's parts list gives the Rate pot as 500K linear, so the drawn value is probably wrong.
- The Depth pot is drawn as 50k; the layout's parts list gives 100K linear.
- The trimmer before the optocoupler is labeled something like P1 / 5k; the layout gives the optoisolator bias trim VR1 as 5K.
- The optocoupler is drawn as UTL5C1, read here as VTL5C1.
| Ref | Value | Normalized | Type | Notes |
|---|---|---|---|---|
| Resistors 17 | ||||
| R1 | 1K | 1k | LED resistor; read from the schematic by eye | |
| R2 | 100K | 100k | read from the schematic by eye | |
| R3 | 4.7K | 4.7k | read from the schematic by eye | |
| R4 | 8.2K | 8.2k | read from the schematic by eye | |
| R5 | 100K | 100k | read from the schematic by eye | |
| R6 | 33K | 33k | read from the schematic by eye | |
| R7 | 10K | 10k | read from the schematic by eye | |
| R8 | 100K | 100k | read from the schematic by eye | |
| R9 | 100K | 100k | read from the schematic by eye | |
| R10 | 10K | 10k | read from the schematic by eye | |
| R11 | 10K | 10k | read from the schematic by eye | |
| R12 | 1M | 1M | read from the schematic by eye | |
| R13 | 100K | 100k | read from the schematic by eye | |
| R14 | 100K | 100k | read from the schematic by eye | |
| R15 | 1.8K | 1.8k | read from the schematic by eye | |
| R16 | 100K | 100k | read from the schematic by eye | |
| R17 | 1K | 1k | read from the schematic by eye | |
| Capacitors 5 | ||||
| C1 | 4.7u | 4.7u | read from the schematic by eye | |
| C2 | 4.7u | 4.7u | electrolytic; read from the schematic by eye | |
| C3 | 47n | 47n | read from the schematic by eye | |
| C4 | 4.7u | 4.7u | electrolytic; read from the schematic by eye | |
| C5 | 1u | 1u | read from the schematic by eye | |
| Diodes 3 | ||||
| D1 | 1N5229 | 1N5229 / 4V3 | 4.3V zener; read from the schematic by eye | |
| D2 | 1N5229 | 1N5229 / 4V3 | 4.3V zener; read from the schematic by eye | |
| D3 | 1N4148 | 1N4148 | read from the schematic by eye | |
| ICs 3 | ||||
| IC1 | LF351 | LF351 | read from the schematic by eye | |
| IC2 | LF442 | LF442 | read from the schematic by eye | |
| IC3 | TL061 | TL061 | read from the schematic by eye | |
| Potentiometers 3 | ||||
| P1 | 5K | 5k | Potentiometer | trimmer, opto bias; read from the schematic by eye |
| Speed | 1K | 1k | Potentiometer | as drawn; see uncertain; read from the schematic by eye |
| Depth | 50K | 50k | Potentiometer | P2; read from the schematic by eye |
| LEDs 1 | ||||
| D4 | LED | LED | 5mm; read from the schematic by eye | |
| Other 1 | ||||
| OK1 | VTL5C1 | VTL5C1 | optocoupler, drawn UTL5C1; read from the schematic by eye | |
Other boards based on the Demeter Tremulator
- Demeter Tremulator Dirtbox Layouts
- Demeter Tremulator Effects Layouts (blog)
- Demeter Tremulator Tagboard Effects