1590B · 4 knobs
Helios (Legacy)
Based on the Pro Co RAT Distortion· 1 other board clones it
- Category
- Distortion
- Controls
- Filter · Distortion · Sweep · Volume
- Difficulty
- Easy
- Price
- see vendor
From the vendor
A distortion pedal with a very distinctive and tight mid-to-high-gain character that made it a staple in the rigs of 1980s hard rock bands.
A classic 80’s distortion pedal, this one needs no introduction. This version can be built with either 3 or 4 knobs (adding the well-known “Sweep” mod), with the Filter knob having two possible orientations to keep things symmetrical.
It also incorporates a switch for the clipping diodes. One side is stock while the other side allows a number of possible modifications, including a “softness” trimmer (clipping threshold control) and plenty of room to stack diodes or use LEDs.
Schematic
The schematic is in the vendor's build document, page 3. Open the build document. No KiCad fragment has been drawn for this circuit yet.
Parts list 36 rows
Report a wrong parse| Ref | Value | Normalized | Type | Notes |
|---|---|---|---|---|
| Resistors 11 | ||||
| R1 | 1M | 1M | ||
| R2 | 1k | 1k | ||
| R3 | 47R | 47 | ||
| R4 | 560R | 560 | ||
| R5 | 1k | 1k | ||
| R6 | 1k5 | 1.5k | ||
| R7 | 1M | 1M | ||
| R8 | 10k | 10k | ||
| R9 | 47R | 47 | ||
| R10 | 100k | 100k | ||
| R11 | 100k | 100k | ||
| Capacitors 13 | ||||
| C1 | 22n | 22n | ||
| C2 | 1n | 1n | ||
| C3 | 30pF | 30p | ||
| C4 | 100pF | 100p | ||
| C5 | 2u2 | 2.2u | ||
| C6 | 4u7 | 4.7u | ||
| C7 | 4u7 | 4.7u | ||
| C8 | 3n3 | 3.3n | ||
| C9 | 22n | 22n | ||
| C10 | 1uF | 1u | ||
| C11 | 100uF | 100u | ||
| C12 | 100n | 100n | ||
| C13 | 47uF | 47u | ||
| Diodes 3 | ||||
| D1 | 1N914 | 1N914 | ||
| D2 | 1N914 | 1N914 | ||
| D5 | 1N4002 | 1N4002 | ||
| Transistors 1 | ||||
| Q1 | 2N5457 | 2N5457 | ||
| ICs 1 | ||||
| IC1 | LM308N | LM308N | ||
| Potentiometers 5 | ||||
| FILTER | 100KA | A100k | Potentiometer | |
| DISTORTION | 100KA | A100k | Potentiometer | |
| SWEEP | 1KB | B1k | Potentiometer | |
| VOLUME | 100KA | A100k | Potentiometer | |
| RPD | 1M | 1M | Potentiometer | |
| Switches 1 | ||||
| SW1 | SPDT | SPDT | ||
| LEDs 1 | ||||
| LED1 | into | INTO | ||
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