У вашего броузера проблема в совместимости с HTML5
This is a video about how to build a router jig to cut circles. It a very simple design but it works really good for most situations.
Click below to check out my new version of this jig. It's a better design, much more versatile, and easier to build. https://youtu.be/QVzy5Th44H4
Be sure to check out my website at: www.redneckdiy.com