I have received communications from several manufacturers about this
issue and am awaiting information from others. I plan on presenting
this during my speech at the 2006 SSA convention.

Interestingly, I picked up the following from the Volkslogger
manual....

=================
"The VOLKSLOGGER has no internal buffer against momentary power
interruptions. This has the advantage that there is no part, which
deteriorates and would have to be replaced every 2-3 years by the
manufacturer. Therefore, the power supply of the instrument has to be
protected against momentary drops below the minimum voltage. In
particular during switching of batteries such voltage drops can take
place, which will lead to a separated flight record during readout.
This means that the recording of the flight consists of several files,
which is accepted reluctantly or not at all by the evaluator.

The circuit shown is meant as an example for a buffered and fused
installation. Alternately it is recommended to use a separate logger
battery (Gel-Cell, 12V, 1.8 Ah), to which no other power consuming
devices are connected."

=======================

Basically the diagram shows the battery connected to the Volkslogger
via a series 0.5A fuse, a series Shottky diode 1N5817 and a parallel
22,000uF capacitor. You can see the diagram in the manaul available
at the web site http://www.volkslogger.de/en/html/volkslogger.html.

The manual states that the logger can be run as low as 9.5vdc (up to
24vdc). However, Mr Johannes Garrecht (designer) stated in his letter
to me that the Volkslogger will run at 7vdc. Impressive.

After I compile all the information and present it at the convention I
will make it available here. Stay tuned.