If HiVolt's set does not have UHF (I deduced this from the lack of UHF antenna terminals on the back of the TV), I am surprised the model number ends with the letter U. That suffix is usually a dead giveaway that a vintage TV has UHF, or in the case of Zenith, a VHF tuner with provisions for optional UHF strips. The latter are installed in unused VHF channel positions, so, depending on how many VHF stations are in your area, you could have as many as nine UHF strips in the tuner (based on three VHF stations; some cities had more, some fewer, when this set was new; if you lived in the New York or Los Angeles areas, for example, your tuner would have five unused channels).
BTW, I too am looking forward to seeing pictures of HV's set in operation. For years (until I moved to a small apartment 12 years ago) I was a collector of old TVs, many of them Zenith, and still have to this day a very strong liking for that brand, although of course Zenith no longer exists today
except as a marketing symbol on flat screens made by LG.