How do I connect a converter box,tv with only coax input, dvd player, and vcr so that vcr...?

Do not know if this will help but i know that thay make a box that will change the rca jacks(red,white,yellow cable) to a coaxl type cause i got one to change my fta which only had rca to coxal so i could watch it on a nother tv cost me about $30.00 canadain not sure what they call it but i got it at wal mart or zallars