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Old September 7th 08, 04:57 PM posted to rec.aviation.soaring
Mike[_8_]
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Posts: 199
Default Intermittant CAI-302a shutdown?

I had a similar problem last year. It turned out to be an intermittent
antenna connection.


On Sep 7, 7:31*am, Frank wrote:
I have been experiencing some intermittant CAI-302a shutdowns, before,
during, and after flights lately. *Here's what I have been able to
determine so far

The shutdown appears to be associated with the CAI-302a sensing that
it's input voltage is too low for normal operation. *When I have been
able to get the CAI-302 to display power supply voltage, I have seen
numbers as low as 4.5VDC, but typically something like 8.8VDC, just
before shutdown. *Switching from the front to the aft battery does not
change the low voltage reading.

I have two brand-new Werker 12V lead-acid batteries, both religously
charged with Battery-Minder Plus chargers, so it is hard for me to
believe that *both* batteries could be loaded down to 8.8V from 12-13
volts without a *lot* of smoke and heat (none detected).

I have eliminated as many loads as I can so far, leaving only the
CAI-302a and my IPAQ 3955 PDA/Cradle (I have plans to eliminate the
PDA & cradle, but haven't done it yet)

The CAI-302a power/data cable appears to be secure at the 302 and at
the power buss.

I have not yet tried to measure the actual 12V battery voltage in
flight, but that's on the list to do. Obviously, this will a PITA, but
do-able.

Any other thoughts? *Anyone else ever have this problem?

Regards,

Frank (TA)