Preamplifiers are only able to deal with the losses that are connected to the output of the amp. They do not improve the performance of the antenna.
Your TV Fool report shows moderate to weak signal levels. A preamplifier such as the RCA TVPRAMP1R would be indicated. If you are splitting the signal and/or have over 50' of coax to push the signal through, then a preamp
may help.
I'd suggest this test before spending money on a preamp,
http://forum.tvfool.com/showthread.php?t=13646