On your concern on a Sylvania, in setting it to Ch 3:
- have you tiried pressing 0 and the 3 on the remotes;
- if the channel up / down jumps 2 to 4, then 3 would have to be added / programmed.
Alternately if the above is not possible:
- the easiest would be to use Ch 4 instead of Ch 3;
- that is if the Verizon device has such a feature. If so, there would be a small selector switch at the rear for Ch3 or Ch4. Set this to Ch 4;
- press the channel up / down of the Sylvania till 04 is displayed.
Alternately (if the above is not applicable) and with better quality of video, use the A / V feature of the TV (only if available on the Sylvania):
- connect yellow, red & white RCA to RCA cables from the rear of the Verizon device to the VIDEO IN and AUDIO IN of the TV;
- set the TV for VIDEO;
Good luck and thank you for using JustAnswer.