I know the odds of someone here being able to answer this are slim but I've been amazed in the past.
I have an older, silver faced, DVR that was made to use with a network, as in an apartment complex. From inspecting the labeling it was manufactured as an HR20-100 and converted afterward to an HR20i-100, network DVR. I have inspected the inside, on the rare chance that I may find a jumper that has, obviously been added. No luck.
DTV technical and commercial technical assistance has been no help. I have no idea where to look next before scrapping the thing.