Hello, I just bought my daughter a different tv for her room. It only has the coax input. The only output I have from the dish box is red white yellow rca cables. I need to convert. Would an old vcr work somehow. If not is there a cheap option. I saw a box called a RF MODULATOR RCA TO COAX CONVERTER but wasn't sure it is was what I needed or not. I was afraid to order it before I ask. I tried to change channels on the setup on the dish box and channels 3 and 4 are greyed out. Anyway any help would be greatly appreciated. Thank you