Spectrum MC-24, Manual

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Spektrum Air Module 21
Flight Log—Optional for the AR9000
Spektrum’s Flight Log (SPM9540) is compatible with Spektrum AR7000, AR7100,
AR7100E, AR9000 and AR9100 receivers. The Flight Log displays overall RF
link performance as well as the individual internal and external receiver link data.
Additionally it displays receiver voltage.
Using the Flight Log
After a flight and before turning off the receiver or transmitter, plug the Flight Log
into the Data port of the receiver. The screen will automatically display voltage
i.e. 6v2= 6.2 volts
Note : When the voltage reaches 4.8 volts or less, the screen will flash
indicating low voltage.
Press the button to display the following information:
A - Antenna fades on internal antenna A
B - Antenna fades on internal antenna B
L - Antenna fades on the left external antenna
R - Antenna fades on the right external antenna
F - Frame loss
H - Holds
Antenna fades—represents the loss of a bit of information on that specific antenna.
Typically it’s normal to have as many as 50 to 100 antenna fades during a flight.
If any single antenna experiences over 500 fades in a single flight, the antenna
should be repositioned in the aircraft to optimize the RF link.
Frame loss—represents simultaneous antenna fades on all attached receivers. If
the RF link is performing optimally, frame losses per flight should be less than 20.
A hold occurs when 45 consecutive frame losses occur. This takes about one
second. If a hold occurs during a flight, it’s important to re-evaluate the system,
moving the antennas to different locations and/or checking to be sure the
transmitter and receivers are all working correctly.
Note : A servo extension can be used to allow the Flight Log to be more
conveniently plugged in without having to remove the aircraft’s hatch or
canopy. On some models, the Flight Log can be plugged in, attached
and left on the model using double-sided tape. This is common with
helicopters, mounting the Flight Log conveniently to the side frame.