Makes sense to have both powered up. But, I'm thinkin that this might be the process:
Internals power the rig, Externals charge the internals while the internals are powering the rig. So, essentially, the externally would be charging the internals, draining more power.
I am visualizing a little troll loading bullets into a big machine gun, while some mutant has the trigger locked down. The more the mutant fires the gun, the more work the troll has to do to keep it loaded. Troll=externals, mutant=internals.
And, about the JB3. I'll test that out this evening and see what happens. That would be interesting to bring the issue up again. Just to remind dumb asses like me!!!
Practice at home is the only way to answer any of these issues. Sucks when it happens out in the field. That is usually the show that the hot girl you have been staring at all show comes up and wants a copy. "Uh...well, my batteries died, but I'd still like your number because I can get it from a buddy, blah, blah, blah." That's like borrowing your buddy's corvette for a first date. It just isn't the same mojo.
Okay, I'm full of wierd metaphors. Gonna go and write some of this down. Maybe I can write a book on metaphors in live recording situations. Would you all buy a copy?
+T love for everyone!!!
-Charlie
*There aren't very many times you can use trolls and mutants in metaphors. Gotta take adventure when given the chance*
The concern I would have is that the battery might be draining extra power out to charge the batteries. My JB3 works just fine without the batteries. I also use a 9v to 5v converter, so that might have something to do with it. But...if the box says to keep the batteries in then if must be law.
Ahhh...just buy two batteries. Problem solved!!!
True that...but you should keep something in mind...I read somewhere in TS.com a loooong time ago that when the JB3 drains dead with exernal power only (no internal batts installed) whatever you're recording is lost if you haven't saved it first. Pretty sure I read that doesn't happen if the JB3 has internal batteries inserted.
But you're right, if the internal batts aren't fully charged, it will just cause the external batteries to drain as they're recharging the internals. That's why it's recommended that you have both batteries fully charged at the start of the show to maximize your run time and minimize the possibility of having the show lost if battery power dies in the middle.
Having said all of this, I have absolutely no clue if the same situation would exist in a 671.
I think I'd do some experimenting at home by recording ambient noise and then running batteries down and seeing what happens in various configurations when the batts die (do you lose any recordings??)...and also using a multimeter (to check voltages on batteries to confirm that the external battery is recharging the internals or just powering the unit when both are connected). I'd want to do this to give myself assurances for wehn I get in the field...partiularly for festivals where I know that I'll be using all my power resources to the max.