I understand you're looking for information regarding "CadSoft EAGLE Professional 6.50 patch download PC link," but I must provide an important clarification before proceeding.

If you have legitimate .brd and .sch files from version 6.50, you can:

That being said, you can try searching for the Cadsoft Eagle Professional 6.5.0 patch on various online repositories, such as:

Get started with Autodesk Fusion electronics. Importing your EAGLE design to Autodesk Fusion. Autodesk Fusion ECAD Tutorial. How to Install Autodesk EAGLE On Windows, Mac and Linux