Ask HN: How do you raise your first round if you can't afford to demo your idea?

Ask HN: How do you raise your first round if you can't afford to demo your idea?
3 by newyearnewyou | 2 comments on Hacker News.
I have an idea, which is expensive to concept $150K (it's a medical hardware product). My background is pretty average, nothing extraordinary, and I don't have a team, but if I can demo the product, I know it will work.