168 degree magnetic compass direction is the other , north , aka , South.
Here is how to aim antennas ,
http://www.kyes.com/antenna/pointing/pointing.html.
Use a Old School magnetic compass to aim antenna.
Channels 7 and 9 in the VHF high band of channels 7 thru 13 are effected in a negative way more by multi-path reflections off of , mountains , hills , buildings and trees / tree leaves , etc. .
Most Digital Tv's have a Signal Strength Meter and some Digital Tv's also have a Signal Quality Meter.
---->Adjust the aim of the antenna for best reception.<----
---->Changing location of antenna can also improve reception.<----
Removing ALL of the amplifier , remove the preamp unit , remove the power injector , remove the power supply.
Can improve reception.
Reason , the amplifier amplifies the main signal and the reflected signals.
The reflected signals are weaker of signal strength then the main signal.
So removing amplification will reduce the signal strength of the reflected signal and then most of the time the reflected signal will be weak enough that the computer in the tuner can correct the reception.
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Digital tuners can develop - Digital Glitches - that are not cleared out with simple channel scans.
Do Double Rescan ,
http://www.wchstv.com/DoubleReScanAlert.pdf.
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