23
Features of the 2.4 GHz Remote Controls
The transmitter technology at 2.4 GHz is fundamentally different
in some aspects from the technology in the 27.35 and 40 MHz
frequency ranges, which up to now have been conventional with
remote control models. The previous approach of using a channel
determined by plug-in crystals is gone, and the transmitter and
receiver work with encoding. The receiver accepts only signals
with the coding from its own transmitter. Each signal from the
transmitter lasts just milliseconds. Before the next signal, a pause is
inserted, which lasts longer than the transmission signal.
Nonetheless, within each second, countless signals are received
and evaluated by the receiver. Signals that the receiver recognizes
as defective (false encoding, symbol sequences that don’t fit the
signal schema etc.) are suppressed and are not passed on as control
commands.
And as the frequency gets higher, the antennas get shorter.
Remote controls using this transmitter technology or model
construction are not subject to fees.
Advantages of the 2.4 GHz Technology
Worth Noting
Although the frequency range used is also divided into channels,
the user doesn’t have to worry about their configuration and has
no influence on it anyway.
Because the same encoding is used by the transmitter and receiver,
interruption by another receiver or a different transmitter will not
occur.
Plug-in crystals are not needed, because the transmitter creates
the currently appropriate frequency using a synthesizer circuit,
as does the receiver, which determines the right frequency for its
encoding.
The old fear of double occupancy of a channel (as when a second
transmitter with excessive range override and interrupts a receiver)
is a thing of the past. An operator can go ahead and switch on a
transmitter and receiver, without negotiating with other model
users.
The data transfer capacity is considerably larger than that of
previous remote controls, which, for example, has a positive effect
on control of the digital servo.
Best of all, at events with a lot of participants, you can always use
your own equipment for settings, tests and conversions, because
there is almost no limit to the number of active transmitters.
At these short wavelengths, obstacles can weaken or interrupt
the passage of radio waves. That means there should be as few
obstacles as possible in the line between the transmission and
reception antennas.
The model’s receiver antenna must be as far away as possible from
electrically conductive parts and very visibly arranged (protruding
from the model) to prevent loss of range.
