125B · 5 knobs
Baja AC30TB EmulatorVerified
Based on the BAJA AC30TB Emulator
- Category
- Preamp / Amp-in-a-box
- Build
- Perfboard
- Layout
- Verified · Effects Layouts (blog) marks it as built and working
- Tags
- Amp Emulator, Baja, Overdrive
From the post
Another one of Bajaman's many amp emulator circuits. It emulates the frequency response of the classic Vox AC30 top boost channel, including power amplifier emulation. It's designed to fit in a 125B with top mounted jacks. Schematic and discussion on FSB here.
The input buffer stage uses a 2SK117 JFET with DGS pinout, but I've throw in an extra pad to use JFETs with GSD pinout (J201, 2N5457, etc). If you're using the 2SK117 you won't need to populate the jumper by Q1, but if you're using a GSD pinout transistor, you will need that jumper.
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 Effects Layouts (blog). No KiCad fragment has been drawn for this circuit yet.
Parts list 34 rows
Report a wrong parseGot parts in a drawer? See what you can build with them.
| Ref | Value | Normalized | Type | Notes |
|---|---|---|---|---|
| Resistors 12 | ||||
| ×3 | 1K | 1k | read from the layout by eye | |
| ×2 | 1.2K | 1.2k | read from the layout by eye | |
| ×4 | 2.2K | 2.2k | read from the layout by eye | |
| ×2 | 2.7K | 2.7k | read from the layout by eye | |
| ×1 | 3.3K | 3.3k | read from the layout by eye | |
| ×2 | 4.7K | 4.7k | read from the layout by eye | |
| ×3 | 10K | 10k | read from the layout by eye | |
| ×1 | 22K | 22k | read from the layout by eye | |
| ×1 | 100K | 100k | read from the layout by eye | |
| ×3 | 1M | 1M | read from the layout by eye | |
| ×1 | 1.5M | 1.5M | read from the layout by eye | |
| ×1 | 390Ω | 390 | read from the layout by eye | |
| Capacitors 11 | ||||
| ×1 | 470pF | 470p | read from the layout by eye | |
| ×1 | 1.2nF | 1.2n | read from the layout by eye | |
| ×1 | 1.8nF | 1.8n | read from the layout by eye | |
| ×1 | 3.9nF | 3.9n | read from the layout by eye | |
| ×1 | 4.7nF | 4.7n | read from the layout by eye | |
| ×1 | 100nF | 100n | read from the layout by eye | |
| ×2 | 220nF | 220n | read from the layout by eye | |
| ×4 | 1uF | 1u | box film; read from the layout by eye | |
| ×1 | 1uF | 1u | electrolytic; read from the layout by eye | |
| ×1 | 22uF | 22u | electrolytic; read from the layout by eye | |
| ×1 | 100uF | 100u | electrolytic; read from the layout by eye | |
| Diodes 2 | ||||
| ×3 | 1N4148 | 1N4148 | read from the layout by eye | |
| ×1 | 1N5817 | 1N5817 | read from the layout by eye | |
| Transistors 2 | ||||
| Q1 | 2SK117 | 2SK117 | JFET; read from the layout by eye | |
| ×2 | ? | ? | BJT, value not given; read from the layout by eye | |
| ICs 2 | ||||
| ×2 | TL062 | TL062 | read from the layout by eye | |
| ×1 | TL072 | TL072 | read from the layout by eye | |
| Potentiometers 5 | ||||
| High | A100K | A100k | Potentiometer | read from the layout by eye |
| Low | A100K | A100k | Potentiometer | read from the layout by eye |
| Cut | B50K | B50k | Potentiometer | read from the layout by eye |
| Gain | B50K | B50k | Potentiometer | read from the layout by eye |
| Level | B100K | B100k | Potentiometer | read from the layout by eye |