If you create your own hardware you need good software tools to doing that. Professional software is too expensive for hobby users but some free software tools doing a good job too.
- SignalIntegrityApp – A GUI software application that is a front-end for the SignalIntegrity library. It can be used for:
- Linear circuit and system simulation.
- Solving for interconnected circuits and s-parameter blocks.
- Virtual probing.
- Network analyzer calibration and calculation.
- Viewing s-parameter files.
- SignalIntegrity – a library of Python packages that allow you to create scripted solutions to various signal integrity problems.
QucsStudio a circuit simulator.
PyBERT is a serial communication link bit error rate tester (BERT) simulator with a graphical user interface (GUI), written in Python and making use of the Enthought Traits/UI packages. It is intended to give students, hobbyists, and curious engineers the ability to play with serial communication link design concepts. It is not intended as a mission critical tool for use by professional serial communication link designers. There are much better tools available for that purpose.
Iowa Hills Software free programs for filters desing.
skrf) is an Open Source, BSD-licensed package for RF/Microwave engineering implemented in the Python programming language. It provides a modern, object-oriented library for network analysis and calibration which is both flexible and scalable.
Eagle free download version – PCB design software for everyone. EAGLE free download is a limited version for hobbyists including 2 schematic sheets, 2 signal layers, and an 80cm2 (12.4in2) board area.
KiCAD is probably now the most popular free tool because it is open source and supported by many of the engineers at CERN and the Raspberry Pi Foundation.
Saturn PCB Design Toolkit is the best freeware resource for PCB related calculations you can find. It incorporates many features that PCB designers and engineers are in regular need of like current capacity of a PCB trace, via current, differential pairs and much more.
Gerbv is a simple to use Gerber file viewer.
Cadence® Allegro® viewer allows anyone to open, view and plot Allegro PCB Editor, OrCAD PCB Editor, Allegro Package Designer, and Allegro PCB SI technology databases without a license.
AppCAD for Windows, a free interconnect impedance calculator. Offer next calculations:
- S-Parameter Analysis and Plotting
- Active Circuit Bias Design
- Cascade Noise and IP3 Analysis
- Transmission Line Analysis
- Signals and Systems
- Complex Math Engineering Calculator