Oh, there's another issue that I've just discovered.
To check the battery, turn the selector knob to 'Control' and depress the thumb safety. The needle in the film speed meter will swing to the right, into the red zone, and stay there. Turn the selector to 'Run', and the camera runs when you depress the trigger. These things happen with I unplug the Power Grip and plug in an external battery.
Saturday I received a newly-recelled hand grip battery from Du-All. I charged it using the charger I also bought, until the LED changed from red to green. Performing the procedure in the previous paragraph, the needle only swings halfway up the meter, and the camera does not run when switched to 'Run'. Du-All says they tested the battery before sending it (in fact, they built it after I telephoned them), and suggest the Power Grip may be faulty. But since some power is getting through (else, the needle wouldn't move), maybe it's something else. I thought I had a dummy battery with an XLR plug so I could test the Power Grip, but I don't or couldn't find it.
Anyone else have this happen? (I did ask about it when I emailed Bernie just now.)