If I understand your posting/description right, you have:
1, a Sanyo TV with only 1 video input;
2. you have a DVD player with only video output; and
3. you have a VCR (which I will assume to be with both video input and output).
Your query, if I may clarify, is how to hook them up so that you need
not connect/disconnect any video cable when you want to switch video
source from either DVD or VCR.
If that is what you want, then connect:
a. audio/video OUT of your DVD to audio/video IN of the VCR;
b. audio/video OUT of your VCR to audio/video IN of the TV.
The above described connection would allow you to:
i. watch DVD movies on your TV (your VCR must be powered ON and set to
Video INput, your TV must be powered ON & set to Video INput);
ii. watch tape movies from your VCR without disconnecting/connecting cables.
Additionally, this arrangement would allow you to record DVD movies in
your VCR. Further, connecting your cable/aerial to the RF INput of your
VCR would allow you to do the same with a TV/Cable program.
Incidentally, if one of your units (TV, VCR, DVD) would only have a
single audio input, it is still possible since some models uses the
white audio RCA connector as either left or mono, the red is right.
You can also use a 2 female RCA to 1 RCA male adapter as shown below to
joint the red/white audio.
Hope this be of some idea/help. Pls post back how things turned out or should you require additional information.
Good luck and kind regards.