You need more powerful Hi-VHF Antenna performance for (Real) Ch12 & Ch13. Rabbit-Ear/Loop
MIGHT make a difference....but it isn't that much better than ANT-1050
You might want to look at adding a DIY Hi-VHF Hourglass-Loop
[Item 21, AWG12 or AWG10 is good, wire size isn't important]....or if that is too large, a simple [Item 7] DIY Hi-VHF Circular Loop
[23-in if 1/4-in Copper Tubing or RG59 Braided Shield] or Square Loop
[18.5-in/side if 1/4-in Copper Tubing] that has significantly higher Gain and much better SWR than Rabbit-Ears:
Use a VHF/UHF Combiner (aka UVSJ)
to combine with UHF signals from ANT-1050 (or whatever UHF Antenna Upgrade you might want to consider, such as Mohu Leaf or even better, Walltenna In-Window 2-Bay Bowtie
We've come up with some DIY Hi-VHF/UHF Antenna Designs OPTIMIZED to work Inside a 2-ft x 3-ft METAL PICTURE FRAME
Most antennas have much lower Gain on the lower end of the UHF Band. The best performance on Ch14 (and Ch17) was provided by mounting an M4 (9.5x9-in) 4-Bay Bowtie inside the Metal Picture Frame
. The best Hi-VHF Gain with somewhat lower UHF Gain, but Excellent SWR for both was provided by the 2-Square Centipede Inside Boxed-Twin-Rectangular-Loop
Element wire size is NOT Critical....you could also use Aluminized Mylar Tape on Cardboard hidden behind the Picture.
Be sure to check out the referenced mclapp websites....he also sell prefabricated M4 4-Bay Bowties (without Reflector, as used here).
Of course, this only works well if you can mount in on a wall so that the Bi-Directional "BEAMS" of the Antenna points roughly towards the desired towers. You might also need to avoid mounting on an exterior wall, which may contain Rebar and/or aluminized Mylar thermal barrier "wrap".
If this is not possible, one of the other, lower Gain Designs may provide better Gain on Ch14 (470-476 MHz), as determined by looking at the off-axis Azimuthal Pattern Charts (let me know if you need help reading these charts).