T o d d P a t t i s t wrote:
David Kinsell wrote:


The capacitor recommendation was an ugly hack recommended
to try to do something about an ill-considered rules change, which
really wasn't an actual rules change.


I agree it's an ugly hack, but a simple one for which I
already had the required components. Plus, it was successful
in solving my problem.

The recommendation in the manual was just to use the monster cap.
That never should have found its way into the manual. Even if
somebody uses a big enough fuse to avoid blowing, caps have a
surge current rating which was no doubt exceeded. Having one
of those things explode in your panel wouldn't be pleasant.


I use a center-off double throw
switch to select battery A or B. The VL is so sensitive to
loss of power that throwing the switch through the center
off position caused a reset half the time. I couldn't
safely check battery voltages or select the new battery
without risking a reset..

A better way of avoiding the problem is just having one battery.
If you have room for two inadequate batteries, then you certainly
could carry one battery big enough to last the whole flight. If
you're not switching, then there's no problem and you don't have
to use all the funny hardware that gets thrown into systems trying
to fix the problem. More importantly, it avoids the need to keep
guessing when the first battery is getting weak, and trying to flip
the switch before the FR resets.

It's sad but somehow amusing that SLA batteries adequate to solve
the problem have been readily available for well over 20 years, but
people seem to keep struggling with it. I fly with a Cambridge 20,
which like most recorders in the field today can't tolerate a power
loss for more than a tiny fraction of a second. But I've never
had a single problem with multiple logs being created. Turn on
the master switch, go fly, and it just works. A 5 A-H battery can
power a normal panel for 6 hours no problem at all. Helps if
you get the voltage right, but that's another discussion . . .


Dave



T o d d P a t t i s t - "WH" Ventus C
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