I need some help. Hopefully someone can help. My daughter's kindergarten class had us hook up a DVD player to their TV. The VCR was already hooked up and the TV only has one input. We hooked the DVD player to the VCR thru the RCA inputs. The VCR is a Panasonic Omnivision Model # PV-1642. It is so old that the Operating Manual is not available online. We can not figure out how to change the input on the VCR to allow the DVD player to work. Does anyone know how to do this?