I Don't have any drawings, but I have seen PVC pipe feeders that seem to work well. First take a length of pipe 3-4 ft long and cut a half circle out of one side on one end. On the other end find a cap or plug to keep out the rain. Paint it to match surrounding area. Attach the pipe to a tree with the notched end towards the ground. The notch should be 2-3 inches above the ground. Fill the pipe with corn or similar sized feed. The corn will pile up on the ground and back up in the pipe and when deer eat some of the corn more will fall out.

Also you can buy battery powered units that attach to 5gal buckets that hang in trees and spread feed at dawn and dusk just like a store bought full unit.

I Have never used the PVC method but I know that it works. We use the 5gal bucket units. Be careful when placing feeders in the woods. Check your game laws before placing any. In our state all non-agricultural feed (ie everything except food plots) and baits must be removed 10 days prior to the first hunting day.
Good Luck

Yes 6" PVC pipe is the cheapest and most effective way to go. You can get real creative with the Y's, T's, Elbows, Reducers and Plugs.