TV Arial - is it digital or not?

Hi there

I have a 2006 Bailey Pageant and I have hooked up my tv (analogue) and I can tune it in ok (channels 1 to 5). If I try and tune in my "digi-box" it does not pick up any channels. I know that the digi-box works ok as I use it in the house. If the Arial is not digital compatible is there a replacement Ariel that you can buy that will replace the old one? I do not want to buy an aerial on a pole etc.

Thanks

Gary