To view the Circuit Builder, Macromedia Shockwave Player is required.

If you do not have this software installed on your PC, after clicking "play" you will be asked if you want to download & install it.

File size: 2.4MB.
Download times: 56k modem 6min, DSL (broadband) 40 seconds, T1 (LAN 1572kb) 13 seconds.