The tvfool radar plot report shows that the Digital Tv stations groups are to the south south east.
Out on the balcony , can you see to the to the south/south east??
Are there close tall buildings that are blocking reception to the , south/south east.
Yes having the antenna higher then the railing will help reception.
Not just peaking over the top , but Actually Higher then the railing.
Aim the ANT751 to the south/south east the best you can and scan for Digital Broadcast Tv channels.
Here is how to aim antennas ,
http://www.kyes/antenna/pointing/pointing.html.
It can also help to clear out the Digital Tv tuner before the Digital Broadcast Tv channel scan.
Digital Tv tuners can develop - Digital Glitches - that are not cleared out with a simple channel scan.
http://www.dtv.gov/rescan.html.
Also for future reference ,
http://transition.fcc.gov/cgb/consumerfacts/rescan.pdf.