This Google Chart requires Internet access by my Raspberry Pi. If the chart here is missing, that suggests my RPi is having troubles accessing the Internet, or I have messed up something. Sorry!
Suggested tips for mapping a profile at heywhatsthat.com:
1) Drag lower right corner of map to enlarge it.
2) Click or enter locations. (Hint: Drag existing "+" symbols.)
3) Click altitude link for each entry, and enter adjustment for antenna height above ground level, e.g., +30.
4) Click "Parameters" below the profile image. Enter "2400" for Frequency. (This reveals the Fresnel zone.)
5) View path profile (clear or blocked), and bearing/range to second station.
6) Click "Clear" or "Backspace" to remove/change locations.
Tip: Use Satellite View to see obstructions (trees, buildings, etc) or tall objects helpful for antenna aiming.