Help With Basic Audio Visual Connections

I returned my Magnavox machine because of this. The only way I managed to hook it up, in the meantime, was to plug my cable TV (coax cable) into an old VCR, then use RCA cables (video and audio in/out) to connect the VCR to the DVD recorder. If you have an old VCR lying around, even if the VCR doesn't work, at least you can use it for this purpose.

I'm guessing there's some sort of converter out there, which would serve the same purpose. But IMHO, it's pretty crazy for manufacturers of DVD recorders not to have an input jack for coax cables, being that cable TV uses them!