okay, so this sucker finally ran out... It got about 50 hours on a 7.5ah batt. So if my calculations are correct:

Battery mAh (7.5) times current draw (x) times .80 = run time (50)

So that would make x=8.3... So the JB3 current draw is 8.3 according to my calculations. Does this sound right? I hope I did it right!

Not quite. Your initial equation is wrong: should divide battery mAH by current draw, not multiply. And 7.5 is the batt capacity in AH, not mAH - should be 7500 mAH:

( battery capacity / current draw ) * .80 = estimated run-time

( 7500 mAH / X ) * .80 = 50 hrs

( 7500 mAH ) * .80 = 50 hrs * X

( 7500 mAH * .80 ) / 50 hrs = X

X = 120 mA current draw

Even taking out the .80 fudge factor since the low current draw improves efficiency we're still only talking 150 mA draw. Seems

*awfully* low. Hmmmmm...what's going on here...can the NJB3 really draw so little current while recording?!?

Alex, did you run a digital signal into the NJB3 this whole time?

Also looks like you got pretty darn close to the theoretical max record space, ~30 hrs - any artifacts in the recordings?