Hi, blu merle:
The channels that your mum will need are in Boston. They are weak 2Edge signals and the coverage in Raymond is very spotty because of the uneven terrain. The tvfool reports are known to be less accurate for 2Edge signals.
NBC is the weakest desired channel. Here is its signal coverage in Raymond. Magenta is very weak; no color is even weaker.
Here is a different Longley-Rice coverage map for NBC. Red is very weak; no color is even weaker.
The terrain profile shows that the curvature of the earth blocks the signal, but some of it can make it to Raymond by refraction. If you use the 91XG, it might help to tilt the front of the antenna up about 15 degrees.
She will need a high gain UHF antenna like the Antennas Direct 91XG or the DB8e with both panels aimed in the same direction, and a preamp like the Channel Master 7778 or Antennas Direct Juice.
If the antenna is outside, the coax shield should be grounded with a grounding block that is connected to the house electrical system ground with 10 gauge copper wire for electrical safety and to reject interference. For further compliance with the electrical code (NEC), the mast should also be grounded in a similar manner to drain any buildup of static charge, but the system will not survive a direct strike.
