Since the Mini Box, Cox has encrypted their TV signals. Therefore, to watch programming with Cox, you'll need a cable box to decrypt their signal. So...yes...every TV will need a box.
If you only want basic channels (ABC, CBS, Fox, NBC), get an antenna. You can visit AntennaWeb.org for who's broadcasting over-the-air in your area.
BEWARE OF THE HYPE! There is no such thing as a "digital antenna." Radio waves are still analog, so a pair of "rabbit ears" can receive HDTV programming.
(This is my post from a previous question)
"HDTV Antenna" is a marketing term created during the HD hoopla. After the digital transition, TV stations didn't abandon their broadcast frequencies. They're still using the same frequencies as their analog days. TV stations only digitized their programming with 1's and 0's.
A broadcast frequency (VHF or UHF) has no idea what it's carrying. It could be NTSC, SDTV, HDTV, ATSC 3.0...it could be anything. The carrier (broadcast) frequency doesn't need to know...it just needs to carry it...carry it to anyone who'll listen.
Therefore, any pair of "rabbit ears" listening on the VHF and UHF bands can receive digital programming from a broadcast station. To watch the program, however, you'll need a digital TV, or converter box, to demodulate the 1's and 0's and display 'em on your screen.
If a pair of rabbit ears doesn't work, you may need an amplified antenna to "reach out" for the signal. Plenty of reviews out there for antennas. Search best OTA HD antenna indoor