(newest Digital logo) http://vintagecomputer.net/digital/Digital_Logo.jpg (from my Alpha Server 2100 4/275)
But I think the original poster said he was looking for the ... d e c ...logo (stacked upright letters)? There might be a cheat...Digital printed a "dec" logo that is very much like the original PDP 1 logo except that the letters are 90 degrees turned couterclockwise on power supplies through the pdp 11 (h742a). Maybe you can work with that. Scan/photo and then use software to turn into the correct position. Here is what I am talking about- http://vintagecomputer.net/digital/PDP11-40_industrial11/pre-cleaning/pre-cleaning_bottom-742a.jpg Billl