2 layers50 × 36 mm
Preamp v2
nyquist-labs/projects
432 electrical-engineering projects by Anna Lin: predict from theory, measure by simulation or real data, compare, explain.
24 parts
2 layers50 × 36 mm
Preamp
nyquist-labs/projects432 electrical-engineering projects by Anna Lin: predict from theory, measure by simulation or real data, compare, explain.
- Size
- 50 × 36 mm
- Copper layers
- 2
- Thickness
- 1.6 mm
- Parts
- 22
- Nets
- 13
- Pads
- 49
- Tracks, vias
- 90, 13
- Pours
- 1
- Routed
- Yes
- KiCad
- KiCad 7 (file 20221018)
- Created
- 30 Sep 2026
- Updated
- 30 Sep 2026
Overview
Preamp is an open-source printed circuit board by nyquist-labs, from the nyquist-labs/projects repository on GitHub. It is a 2-layer board of 50 × 36 mm with 22 parts on 13 nets, routed with 90 tracks and 13 vias.
It is built around the NE5532. Its parts include 8 resistors, 6 capacitors, 3 connectors and 1 IC. It belongs with the audio and music boards of this library.
Main components
1README
README.mdNyquist Labs
Created and maintained by Anna Lin. Nyquist Labs is Anna Lin's independent project; it is not affiliated with any company or organisation of a similar name.
432 electrical-engineering projects Two tracks: a hands-on signal lab (circuits, power electronics, digital logic and HDL, DSP, communications, RF, control, embedded systems, biosignals, PCB design, browser tools) and an applied-mathematics track (complex analysis to information theory), built from two public project lists.
At a glance
| Projects | 432 (index: PROJECTS.md, PROJECTS.csv) |
| Predicted-vs-measured comparisons | 2257 |
| Comparisons with an explicit tolerance | 1426, of which 1357 within tolerance and 69 outside it (flagged no in the project table — wrong first guesses, rules of thumb that do not hold, or tolerances set tighter than the numerics) |
| Projects using real or recorded data | 90 |
| Website | docs/ (enable GitHub Pages on the docs folder) — searchable index and the interactive tools |
Tracks and categories
| Track | Category | Projects | Comparisons | Within tolerance | Real data |
|---|---|---|---|---|---|
| Applied Mathematics — 218 projects in electrical engineering | A. Complex analysis & phasors | 18 | 96 | 88/92 | 1 |
| Applied Mathematics — 218 projects in electrical engineering | B. Fourier analysis & transforms | 25 | 132 | 124/129 | 4 |
| Applied Mathematics — 218 projects in electrical engineering | C. Differential equations | 18 | 101 | 88/91 | 0 |
| Applied Mathematics — 218 projects in electrical engineering | D. Linear algebra | 18 | 91 | 76/80 | 1 |
| Applied Mathematics — 218 projects in electrical engineering | E. Probability & stochastic processes | 20 | 105 | 96/102 | 0 |
| Applied Mathematics — 218 projects in electrical engineering | F. Optimisation | 15 | 51 | 41/43 | 1 |
| Applied Mathematics — 218 projects in electrical engineering | G. Numerical methods | 18 | 79 | 70/70 | 0 |
| Applied Mathematics — 218 projects in electrical engineering | H. Discrete math, finite fields & coding | 20 | 167 | 19/19 | 1 |
| Applied Mathematics — 218 projects in electrical engineering | I. Control theory | 16 | 136 | 103/104 | 0 |
| Applied Mathematics — 218 projects in electrical engineering | J. Statistics & learning on real signals | 20 | 150 | 87/97 | 20 |
| Applied Mathematics — 218 projects in electrical engineering | K. Fields, vector calculus & geometry | 15 | 111 | 106/107 | 0 |
| Applied Mathematics — 218 projects in electrical engineering | L. Information theory | 15 | 91 | 62/63 | 8 |
| Signal Lab — 214 electrical-engineering projects | A. Analog circuit design & simulation | 25 | 120 | 68/76 | 0 |
| Signal Lab — 214 electrical-engineering projects | B. Power electronics | 12 | 73 | 54/56 | 1 |
| Signal Lab — 214 electrical-engineering projects | C. Digital logic & HDL | 22 | 120 | 16/17 | 0 |
| Signal Lab — 214 electrical-engineering projects | D. Digital signal processing | 25 | 116 | 25/27 | 4 |
| Signal Lab — 214 electrical-engineering projects | E. RF, radio & satellites (real signals) | 22 | 80 | 21/21 | 12 |
| Signal Lab — 214 electrical-engineering projects | F. Communication systems | 15 | 65 | 32/35 | 0 |
| Signal Lab — 214 electrical-engineering projects | G. Electromagnetics & device physics | 15 | 63 | 55/57 | 0 |
| Signal Lab — 214 electrical-engineering projects | H. Embedded systems (simulated) | 20 | 72 | 20/21 | 0 |
| Signal Lab — 214 electrical-engineering projects | I. Control systems | 15 | 52 | 21/28 | 0 |
| Signal Lab — 214 electrical-engineering projects | J. Biosignals & HCI (real patient data) | 21 | 53 | 7/9 | 19 |
| Signal Lab — 214 electrical-engineering projects | K. Interactive tools & web apps | 12 | 62 | 38/40 | 10 |
| Signal Lab — 214 electrical-engineering projects | L. PCB design | 10 | 71 | 40/42 | 8 |
Repository layout
eelab/ shared engine: Project/README generator, circuit simulator (MNA), HDL flow (Icarus + Yosys),
PCB toolkit (footprints, router, DRC, Gerber/KiCad export), field solvers, coding & comms,
from-scratch ML (eelab.ml), dataset fetchers with caching
projects/<track>/<category>/<ID>-<slug>/
project.py META (problem, theory, method) + run(p): predict → measure → compare → discuss
README.md generated: prediction-vs-measurement table, figures, discussion
figures/ data/ results.json (hdl/, web/, fab/, kicad/ where relevant)
run_all.py runs projects in parallel and rebuilds PROJECTS.md/.csv and docs/
site/template.html website template; docs/ is the generated site
tools/show.py print a project's results table in the terminalRunning it
python3 -m venv .venv && source .venv/bin/activate
pip install -r requirements.txt
python run_all.py # everything (first run downloads datasets into data_cache/)
python run_all.py --only AM-150 SL-205
python run_all.py --track applied-math --category H
python run_all.py --index-only # rebuild the index and website from existing results
python tools/show.py AM150 # results table in the terminalRequirements: Python 3.11+; Icarus Verilog (brew install icarus-verilog / apt install iverilog) for the HDL projects; Node.js to verify the JavaScript of the browser tools. A full run takes roughly half an hour on a laptop with 8 cores; a handful of projects (genetic-algorithm antenna design, the NumPy CNN, spherical-harmonic expansions) take several minutes each.
Datasets and licences
Datasets are downloaded at run time and cached locally; they are not redistributed in this repository and remain under their own licences. Please cite the original sources.
| Dataset | Source | Licence | Link |
|---|---|---|---|
| MIT-BIH Arrhythmia Database | PhysioNet (Moody & Mark 2001) | ODC Attribution License | https://physionet.org/content/mitdb/ |
| MIT-BIH Noise Stress Test Database | PhysioNet (Moody et al. 1984) | ODC Attribution License | https://physionet.org/content/nstdb/ |
| EEG Motor Movement/Imagery Dataset | PhysioNet (Schalk et al. 2004) | ODC Attribution License | https://physionet.org/content/eegmmidb/ |
| Sleep-EDF Expanded | PhysioNet (Kemp et al. 2000) | ODC Attribution License | https://physionet.org/content/sleep-edfx/ |
| CHB-MIT Scalp EEG Database | PhysioNet (Shoeb 2009) | ODC Attribution License | https://physionet.org/content/chbmit/ |
| BIDMC PPG and Respiration Dataset | PhysioNet (Pimentel et al. 2016) | ODC Attribution License | https://physionet.org/content/bidmc/ |
| Examples of Electromyograms | PhysioNet | ODC Attribution License | https://physionet.org/content/emgdb/ |
| Human Activity Recognition Using Smartphones | UCI ML Repository (Anguita et al. 2013) | CC BY 4.0 | https://archive.ics.uci.edu/dataset/240 |
| EMG data for gestures | UCI ML Repository (Lobov et al. 2018) | CC BY 4.0 | https://archive.ics.uci.edu/dataset/481 |
| Free Spoken Digit Dataset | Jakobovski et al. | CC BY-SA 4.0 | https://github.com/Jakobovski/free-spoken-digit-dataset |
| Li-ion Battery Aging Datasets | NASA Ames Prognostics Center of Excellence (Saha & Goebel 2007) | NASA open data | https://www.nasa.gov/intelligent-systems-division/discovery-and-systems-health/pcoe/pcoe-data-set-repository/ |
| Satellite observation recordings (NOAA APT) | SatNOGS Network | CC BY-SA 4.0 | https://network.satnogs.org/ |
| Orbital elements (TLE) | CelesTrak | public | https://celestrak.org/ |
| WSPR propagation spots | WSPRnet via wspr.live | see provider terms | https://wspr.live/ |
| Mode S / ADS-B test capture | dump1090 test files (antirez) | BSD-3-Clause | https://github.com/antirez/dump1090 |
| 'Hello' pronunciation audio | Wikimedia Commons | CC BY-SA | https://commons.wikimedia.org/wiki/File:En-us-hello.ogg |
| KiCad footprint library (reference footprints) | KiCad project | CC BY-SA 4.0 with exception | https://gitlab.com/kicad/libraries/kicad-footprints |
| Alice's Adventures in Wonderland | Project Gutenberg eBook #11 | public domain | https://www.gutenberg.org/ebooks/11 |
Licence
Code and generated documents: MIT (see LICENSE). Third-party data: see above.
Parts
22| Qty | Value | Footprint | References |
|---|---|---|---|
| 4 | 100k | eelab:C_0805 | R1, R2, R5, R6 |
| 4 | MountingHole_3.2mm | eelab:MountingHole_3.2mm | H1, H2, H3, H4 |
| 2 | 100 | eelab:C_0805 | R4, R8 |
| 2 | 100n | eelab:C_0805 | C3, C4 |
| 2 | 10k | eelab:C_0805 | R3, R7 |
| 2 | 10uF | eelab:C_1206 | C5, C6 |
| 2 | 1uF | eelab:C_0805 | C1, C2 |
| 1 | +12/GND/-12 | eelab:PinHeader_1x03_P2.54mm | J3 |
| 1 | IN L/GND/R | eelab:PinHeader_1x03_P2.54mm | J1 |
| 1 | NE5532 | eelab:SOIC-8 | U1 |
| 1 | OUT L/GND/R | eelab:PinHeader_1x03_P2.54mm | J2 |
Questions
How big is the Preamp PCB?
It measures 50 × 36 mm and has 2 copper layers, 1.6 mm thick.
What parts does the Preamp use?
22 parts, built around the NE5532. The full list of its parts is on this page, with links to each part's symbol and footprint where PCBKit's library has them.
Where can I download the Preamp KiCad files?
From the nyquist-labs/projects repository on GitHub, at the commit this page was made from: the board is projects/signal-lab/L-pcb-design/SL205-amplifier-board/kicad/preamp.kicad_pcb. PCBKit opens the board in the browser, with nothing to install.
Can I use the Preamp design in my own project?
Its repository states no licence, so its author keeps all rights: ask nyquist-labs before reusing the design.
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