I have a HP82161A cassette drive which has no battery pack (I assume it died some long time ago). The unit is now powered by 4xD cells (~6v) but the battery warning is displayed intermittently during operation.
Is this because of the higher internal resistance of these cells (as opposed to nicads) or is the original nicad pack a higher voltage?
I'd like an indication of the nominal output voltage of the nicad pack before I increace the voltage to approx 7.5 volts by the addition of another cell.