Bill Burk has it right, I think. I also use D76 1+1, 20C or close to, +/- 10-12 minutes. I still use this to process Panatomic, as I have a stash of the stuff left.
What ASA/EI/ISO did you shoot it at? I use mine at either 25 or 20 depending on light conditions. Panatomic always responded well to harsh Australian sunlight but for my needs -10%-15% processing times produced the best negatives.
It's very old film (discontinued in the late 1980s) and will need a bit of a contrast boost. Your images should be fine, tho. My results show very little base fog, in fact barely enough to level out the mid tones in enlarging, as a sort of built-in grey mask.