Since it's such a large number and difficult to comprehend Voyager 1 is about 116 AU away. 1 AU is the distance from earth to the sun (150,000,000 km). Earths circumference is 40,000 km. Space is big.

Also, a neat summary of the computers on Voyager can be found here: http://voyager.jpl.nasa.gov/faq.html

I'm still trying to track down the article on the comm used.