Steve Hagar wrote:
> One unusual anomoly was found however. Any
> input from the list would be appreciated. The electric horizon gyro is
> driven off of the essential electrical bus. When the alternate feed switch
> is turned on the gyro runs up normally and the off flag indicator goes
> away. The alternate feed is a direct connection to the battery. When the
> essential bus is run through its normal feed, which is through the primary
> bus through a big diode an anomoly is seen.
Sounds normal. As I recall, the flag voltage for the RC Allen's AH is greater
than
for its DG too. Instrument shop lady told me normal at about 11.9V to unflag.
The diode drop is the culprit. My alternative to an essential bus is the
ability to merely switch every optional device off fwg an alternator failure.
Flag should go away with alternator online, but depending upon its volts at
lower
RPMs and total load. But which may thus be unsatisfactory for a night IFR
approach....
Best,
Fred F.
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