I am running some power tests on the DR70-D.
The setup is :
-- Anker 2G E4 13000mAh Usb battery,
-- recording all four channels,
-- at 96/24,
-- with 4 Akg Blue Line mics with phantom power on.
Measured through a small Usb inline meter, the results are :
-- Voltage (average) 5.24V
-- Intensity (average) 0.63A
This translates into 3.30W power used.
Supposing that the Usb batteries specs are given for 3.5V rather than 5V, 13000mAh would give 13.8 hours theoretical run time. This seems more or less in line with the test running as I just lost the 3 diode (there are four of them) on the battery so half the diodes (power) left after 7 hours...
-- Only one diode left after 9 hours and 50 minutes...
-- After a little less than 11 hours the card (32GB) was full. The DR70-D did not like being stopped that way. Powered it down, changed the the card, formatted it but it would not restore phantom power to the mics. Powered it down and then up again, same result. I had to stop it and remove the power source for a minute before starting again and getting the phantom back...
-- After 13 hours and 30 minutes the one remaining diode began flashing...
-- The external battery last diode went off after 13 hours and 45 minutes and the recorder switched to internal batteries. This is 13.75 hours : very close to the 13.8 hours computed before starting !