G-23
The Flight Log is compatible with JR R921 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 on the
JR R921 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 that 20.
A hold occurs when 45 continuous (one right after the
other) 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 more conveniently be 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.
Flight Log—Optional for JR R921 Receiver
