Please post a tvfool radar report.
Make the antenna height the reference 25 feet antenna height or higher if the antenna is higher.
What is the make and model of the antenna??
If the antenna uses a separate matching transformer (balun) , replace with a New matching transformer.
As a Test of reception , connect a NEW continues length coax to the New matching transformer and run the New coax through a open door or window direct to 1 Tv.
Digital tuners can develop - Digital Glitches - that are not cleared out with simple channel scans.
Do Double Rescan ,
http://www.wchstv.com/DoubleReScanAlert.pdf..
______________
Weather/Water gets into outside connections and coax.
For outside coax use the coax that has the Compression type connectors on the ends of the coax not the old crimp type connectors.
ALL outside , coax , connectors , connections , are suspect of being bad , and as a matter of fact , All , coax , connectors , connections , are suspect of being bad through out the complete system.
NEVER use vinyl electrical tape outside , the tape does not hold up to weather/water , it takes in water and holds water inside , this is not good for connections.
-->Use
http://www.coaxseal.com.<--