It depends how 'old' we're talking about. Many older TV's only have one input which was/is coaxial cable. If this is the the case, you have two options. You unplug the DirecTV when you want to use the VCR and vice versa, or you can go to Radio Shack or best buy and they sell junction boxes to give you more inputs for the TV. If TV has more than one input just plug VCR into other input. When you want to watch VCR you just change input. Hope this helps!
K u need a RG-6 wire (coax wire), RCA Jacks (red, white and yellow) or hdmi if its HD... Basically u have ur tv and Directv receiver. U need to hook up ur DVD player between them... I was trained to treat this like a hamburger.. Ur tv and r receiver is the bun... Ur DVD player is the meat.. All wires go to the DVD player.. so take a wire to the reciever, then take a wire from r receiver to the DVD player... Hope this didn't sound to silly, but its helped me in my 11 years as a tech... Let me know if u need more help... THANK U..