First off, remove the spaces between CHART and the square brackets. Insert a URL between the two. The chart's URL must have http:// removed to work.
To find out an image location, right click on the image, and select Properties if you are using IE, and copy the address. If using Firefox, select Copy Image Location.
Don't ask me where I found this particular chart at stockcharts, I just took a chart I found here at iHub (in the iBox at the FASC board for future reference) and replaced the existing ticker with GSPG's.