Assuming you used the standard YELLOW-WHITE-RED RCA cable, between the unit and the TV, the colours of each of the plugs should match both the outputs on the rear of the unit and the respective inputs at the rear of the TV. The TV must also be on an AV input 'channel' to receive the connected unit. (for example, AV1 or VIDEO 1)
Try changing the RCA cables - just in case the ones you currently have are defective in some way.
Being a combo unit, there should be a DVD-VCR common output on the rear - using RCA cable, the YELLOW is video, the WHITE is left channel, the RED is right - these MUST match the input on the TV, and the TV AV input must be selected in order to view the pictures and audio from the unit. To enjoy both VCR and DVD, using the RCA connection, the common output on the rear of the combo unit is recommended.
Better quality video is possible using S-Video cable (available from electronics stores such as Radio Shack etc. but this does not provide audio; you would still require RCA RED-WHITE cable for that, and your TV may not have S-Video input). Your TV may have a TV/AV button on the front - select the correct AV 'channel' with that if necessary.
It makes sense to check everything twice before assuming anything is broken.
RCA DRC8300N DVD...
on Sep 03, 2012