Hobbyists and engineers often struggle to find reliable resources for refurbishing vintage oscilloscopes.
Develop a comprehensive guide with step-by-step instructions, troubleshooting tips, and sourcing parts.
Sell the guide as an ebook or offer a subscription for updates and advanced tutorials.
Start with a basic guide for a popular model and expand to more devices over time.
The risk is limited audience size, but enthusiasts are often willing to pay for niche content.