User manual

3. Antennas and Satellites
All Hyperion receivers are “full range”. However the range of any receiver is affected by the
number of antennas (aerials) and their orientation, as well as by the installation in the
model, making comparisons difficult. Some Hyperion receivers and satellites have one
short active antenna wire, while others also have a second identical “reflector” wire. Some
come with longer twin diversity antennas or have them as an option. For the strongest and
most reliable reception there are a number of good practices to follow.
For receivers and satellites with short wire antennas:
1. The wire(s) should stick reasonably straight out from the receiver/
satellite; where there are two, they should be in an approximately straight
line. Antennas that are bent along the receiver/satellite board may have
range reduced by 10-15%.
2. If a satellite is connected, it should be located as far as possible from the
main receiver, not right next to it.
3. If a satellite is connected, most reliable reception is obtained when the
satellite antenna and main receiver antenna are at right angles.
The larger non-diversity receivers (e.g., 7, 8- and 10-channel) do not have a
second short antenna wire, as the circuit board serves the reflector function.
A small receiver with only a single antenna wire (including satellite-enabled
receivers when operated without a satellite) will generally have less range by
about 10-15% than an equivalent twin short antenna wire version. This is still
ample range for normal flying.
For receivers and satellites with diversity antennas:
Receivers and satellites with diversity have two antennas made of coaxial cable
with the last 32mm of outer insulation and conductive sheath removed to create
a white or silver active portion (the antenna proper).
The antenna cables are connected to an electronic switch that selects the one
currently with the stronger available signal. The receiver will switch antennas
very quickly if the signal from the one it is using starts to drop in strength below
the signal from the other antenna. The switching occurs within 300mS and no
signal is lost during the switching period. This antenna-switching strategy is
commonly called “diversity” in the RC world.
A satellite does not significantly increase the maximum possible range. Rather, as
a separate stand-alone receiver it increases the probability that a reliable signal
will be obtained at all times no matter the orientation of the model. The main
receiver selects the stronger of its own best signal or that of the satellite. Note
that if both the receiver and the satellite have diversity antennas this gives up to
four separate signal sources for the receiver/satellite combination.
The antennas we use for radio control radiate (and receive) in all directions, but
the signal is much weaker off the ends of the antenna (the active portion of the
cable) than "broadside" to it.