check out this diagram
, paying close attention to the audio video cable hookups.
assume the cable tv box represents the converter box
you are going to come out of the converter box audio and video outputs into the new magnavox dvd/vcr combo audio and video inputs.
Then out of the new magnavox dvd/vcr combo outputs to the inputs on the tv if it has such inputs. The TV will have to operate on the video input 1 or 2 if the tv has such a thing, use the remote for the tv to adjust the input signal to line in 1 or 2 depending on what it has.
If the tv has no coaxial input or audio video inputs then you might have to use an adapter, you can get these from radio shack.
You say it will not record from the tv, but in all actuality the dvd vcr combo is getting the signal from the converter box not the tv, do you understand what I mean here?
So the dvd vcr combo gets input from the converter box so you will have to set it to view signal from the line input you have plugged in from the converter box. line 1 or 2 or whatever the input is.
the tv will have to be set on the line input to view the signal from the dvd vcr combo.
That is as easy as I can put it. Study the diagram closely. You will see what I mean.