You need one of these.

http://www.walmart.com/ip/RCA-VH54-LVH54N-RCA-VH54-LVH54N-Indoor-Matching-Transformer/20588615

EDIT: Note that's a completely outrageous price for one. For example:

http://www.cnaweb.com/indoor-nickel-matching-transformer.aspx?gclid=Cj0KEQjw4fCqBRDM1ZKhk5jfo6IBEiQAZQ97OHh6NLL77trhylPIVvI0kVZ-8fJV1F2YJbTFDm6KpBIaAuAW8P8HAQ

Used to be you couldn't go through any junk drawer without finding one of these things, but I guess it's been 20 years since people commonly needed them.