Enclosure not stated · 2 knobs
John Hollis FrobnicatorVerified
Based on the John Hollis Frobnicator
- Category
- Octave / Pitch
- Build
- Vero· 18×19· 18 cuts, 9 links
- Layout
- Verified · Tagboard Effects marks it as built and working
- Tags
- Noise, Octave, Tremolo
From the post
This one is definitely verified, but:
The LFO section is *very* sensitive to both voltage and current, so if your board doesn't fire up right away (which happened with my second build too), you should consider doing a little daughterboard with 9V regulator, 8V2 zener and a 10-50 trimmer to get the LFO going. That being said - this is not a project for beginners.
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Mr. Hollis has been known for his modulation circuits. This one seemed like an interesting build so i drew it up. Once again. I'm more or less out of sources for the demos and so on. But i have a hunch that this may be 1:1 with two knob version of Copilot FX Android... Anyway. The circuit does tremolo from mild to wild and flick of a switch turns it into super mean ring modulator - with lots of good stuff on the sweep. Or so i'm told.
Schematic
This is a board layout, a drawing of where each part goes, and the post may link the schematic it was drawn from. Open the layout at Tagboard Effects. No KiCad fragment has been drawn for this circuit yet.
Parts list 27 rows
Report a wrong parseGot parts in a drawer? See what you can build with them.
| Ref | Value | Normalized | Type | Notes |
|---|---|---|---|---|
| Resistors 10 | ||||
| ×4 | 10K | 10k | read from the layout by eye | |
| ×2 | 10M | 10M | read from the layout by eye | |
| ×2 | 100K | 100k | read from the layout by eye | |
| ×1 | 330K | 330k | read from the layout by eye | |
| ×1 | 470K | 470k | read from the layout by eye | |
| ×1 | 22K | 22k | read from the layout by eye | |
| ×1 | 220K | 220k | read from the layout by eye | |
| ×1 | 47K | 47k | read from the layout by eye | |
| ×1 | 4.7K | 4.7k | read from the layout by eye | |
| ×1 | ? | ? | LED resistor, value not given; read from the layout by eye | |
| Capacitors 6 | ||||
| ×2 | 100nF | 100n | read from the layout by eye | |
| ×1 | 47nF | 47n | read from the layout by eye | |
| ×1 | 2.2nF | 2.2n | read from the layout by eye | |
| ×1 | 1uF | 1u | electrolytic; read from the layout by eye | |
| ×1 | 47uF | 47u | electrolytic; read from the layout by eye | |
| ×1 | 100uF | 100u | electrolytic; read from the layout by eye | |
| Diodes 1 | ||||
| D1 | 1N4148 | 1N4148 | read from the layout by eye | |
| Transistors 1 | ||||
| Q1 | BC184L | BC184L | use MPSA18 or 2N5089; read from the layout by eye | |
| ICs 2 | ||||
| IC1 | CA3080 | CA3080 | read from the layout by eye | |
| IC2 | TL062 | TL062 | use TL072 for lower noise level; read from the layout by eye | |
| Potentiometers 2 | ||||
| Depth | B10K | B10k | Potentiometer | read from the layout by eye |
| Freq | A100K | A100k | Potentiometer | read from the layout by eye |
| Trimmers 1 | ||||
| VR1 | 100K | 100k | flat fits too, install 10M first; read from the layout by eye | |
| Switches 1 | ||||
| Ring/Trem | SPDT | SPDT | toggle, On-Off or On-On; read from the layout by eye | |
| LEDs 3 | ||||
| D2 | red LED | RED LED | read from the layout by eye | |
| D3 | red LED | RED LED | read from the layout by eye | |
| D4 | red LED | RED LED | read from the layout by eye | |