DL4 question

[Tim Nelson <tcn62@ici.net>]

As I understand it, the DL4 can operate either on the "pregnant extension
cord" power supply or with 4 C batteries.

I'm also under the impression that the user programmable settings survive
power down (ie, they're not volatile)...

Here's my question for one of you who're already honeymooning with yours:
Do the user settings remain after power down if you DON'T have the 4 C
batteries installed, or while changing them?

Also, what's the sampling rate?

Tim