For most, Seiki isn’t a household name in consumer electronics, but when they release (later this month) a 39-inch 4K HDTV for $699 they will become one. The 39-inch, affordable 4K option (model SE39UY04) has a max resolution of 3840×2160, a refresh rate of 120hz at 1080p, and 30hz. The budget 4K TV also has built-in digital and…