http://74.125.95.104/search?q=cache:53Rl8eWp_6EJ:www.bigmech.com/misc/c64mods/noisereduction.html+commodore+64+noise&hl=en&ct=clnk&cd=1&gl=ca&client=firefox-a If that link doesn't work, email me, I have it saved.
This link works for me:http://www.bigmech.com/misc/c64mods/noisereduction.html