Enclosure not stated · 1 knob
EHX Doctor QVerified
Based on the Electro-Harmonix Doctor Q· 2 other boards clone it
- Category
- EQ / Filter
- Controls
- Sensitivity
- Build
- Vero· 15×16· 13 cuts, 7 links
- Layout
- Verified · Tagboard Effects marks it as built and working
- Tags
- Bass, Electro Harmonix, Filter
From the post
Should work miracles on guitar too...
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 18 rows
Report a wrong parseGot parts in a drawer? See what you can build with them.
Check before you build · 2 values the reader of this layout was not sure of
- 50nF (×2: left of IC1 and centre of the board): printed clearly, unusual value
- 5nF (×2: lower centre and right of centre): printed clearly, unusual value
| Ref | Value | Normalized | Type | Notes |
|---|---|---|---|---|
| Resistors 6 | ||||
| ×5 | 47K | 47k | read from the layout by eye | |
| ×3 | 470K | 470k | read from the layout by eye | |
| ×1 | 2.2M | 2.2M | read from the layout by eye | |
| ×1 | 22K | 22k | read from the layout by eye | |
| ×1 | 100Ω | 100 | read from the layout by eye | |
| ×1 | 47Ω | 47 | read from the layout by eye | |
| Capacitors 5 | ||||
| ×2 | 50nF | 50n | read from the layout by eye | |
| ×2 | 5nF | 5n | read from the layout by eye | |
| ×1 | 1nF | 1n | read from the layout by eye | |
| ×1 | 10nF | 10n | read from the layout by eye | |
| ×2 | 10uF | 10u | electrolytic; read from the layout by eye | |
| Diodes 2 | ||||
| D1 | 1N914 | 1N914 | read from the layout by eye | |
| D2 | 1N914 | 1N914 | read from the layout by eye | |
| Transistors 1 | ||||
| ×1 | BC239C | BC239C | legend: Try 2N3904; read from the layout by eye | |
| ICs 1 | ||||
| IC1 | ECG778 | ECG778 | legend: try TL072 or similar; read from the layout by eye | |
| Potentiometers 1 | ||||
| Sensitivity | B100K | B100k | Potentiometer | read from the layout by eye |
| Trimmers 1 | ||||
| ×1 | 25K | 25k | read from the layout by eye | |
| Switches 1 | ||||
| Bass/Norm | DPDT on/on | DPDT ON/ON | toggle; legend says 2PDT On-On; read from the layout by eye | |
Other boards based on the Electro-Harmonix Doctor Q
- Electro Harmonix Doctor Q Experimentalists Anonymous
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