The first release of the Harrisburg_PA.kmz file had a corrupted overlay file for WHP-DT.  Since Google Earth could not decode and display the image, this caused the coverage map to show up as a large red X, instead.  The file has now been fixed and is availabe for download.  If you downloaded this file previously or see the large red X for WHP-DT, then you should download the file again for the fully working version.  It is available in the Coverage Maps area as MSA number 66.