6.
C
-
OUNTRY
SPECIFIC RESTRICTIONS
!
Legal note: transmitting apparatus must only be set up
and operated on frequencies / transmission channels which
are approved for the country in which it is to be used.
!
Important: in particular countries the module may only
be used within a restricted frequency range.
In certain countries the operation of 2.4 GHz RC systems with
an output power of 100 mW EIRP is only permitted within a
restricted frequency range. For this reason the HFMG4 M-LINK
2.4 GHz RF module offers the option of limiting the frequency
range ( 16.).
You can find an overview of the countries affected by this
restriction in the separate sheet entitled "Operating the 2.4 GHz
M-LINK System with Restricted Frequency Range".
7.
T
M-LINK
HE
TRANSMISSION SYSTEM
M-LINK is a transmission system designed by MULTIPLEX. It
operates on the 2.4 GHz ISM band, and exploits modern FHSS
technology (FHSS = Frequency Hopping Spread Spectrum).
Automatic RF channel management:
With this system it is no longer necessary for the operator to
select the RF channel manually (plug-in crystals, Synthesizer).
2.4 GHz Spread Spectrum systems automatically divide up the
frequency spectrum, and this eliminates the need for conven-
tional frequency monitoring. Same-channel interference (as is
possible on the 35, 40, ... MHz band) is virtually impossible. The
first time the system is used you just have to carry out a simple
binding procedure to link the transmitter to the receiver. From
this moment on the receiver only responds to the signals from
your specific transmitter.
FHSS technology:
The transmitter and receiver jump from channel to channel every
few milliseconds, maintaining the same rhythm; the data is
transmitted during a fraction of this period. The resultant brief
period of channel occupation minimises signal conflicts, and
suppresses interference. Even if data packets are lost on par-
ticular channels, the constant high-speed hopping to the next
channel makes any interruptions unnoticeable to the pilot.
Good data security / Transmission security:
The enormous bandwidth available on 2.4 GHz makes it pos-
sible to transmit much greater quantities of data than is possible,
for example on the 35 MHz band (bandwidth on 2.4 GHz =
83.5 MHz; on 35 MHz = 1 MHz). Digital modulation in conjunction
with sophisticated error-checking in the receiver guarantee out-
standing data quality.
Good resistance to interference:
Typical interference sources in the model, such as electric
motors, and electronic devices such as speed controllers, petrol
engine ignition systems etc., have an interference spectrum
whose maximum frequency is significantly below the 2.4 GHz
range. It is virtually impossible for 2.4 GHz systems to suffer
interference from such sources, and this provides a further im-
provement in security.
Fast, accurate transmission:
MULTIPLEX M-LINK is a digital transmission system offering a
maximum of sixteen servo channels with a resolution of 12 bits
(3872 steps). Background noise has no effect on servo signal
accuracy right up to the limits of range. Resolution, centring
precision and with it general accuracy of control are at a con-
stant high level up to the effective limits of range. M-LINK's
digital encoding allows both HOLD and FAIL-SAFE to operate
very accurately. The servo pulse rate of 21 ms (16-channel mode)
can be reduced to 14 ms (12-channel mode - Fast Response).
Feedback capability / Telemetry:
Operating Instructions
HFMG4 M-LINK 2.4 GHz RF Module
The 2.4 GHz ISM band offers the possibility of transmitting data
from the model back to the transmitter. If you use a telemetry-
capable receiver, the transmitter emits an audible signal to warn
you when the receiver battery is almost flat.
If you also install the MULTIPLEX Telemetry-Display (# 4 5182),
the screen shows you the connection quality (LQI = Link Quality
Indication) in addition to the actual voltage of the receiver power
supply.
The Telemetry-Display can also output additional telemetry data,
such as current, voltage, altitude or speed values - depending
on the sensors connected to the system.
The Telemetry-Display is capable of displaying a maximum of
sixteen telemetry values.
Visual and audible warnings are generated via the Telemetry-
Display; the warning sounds are produced either by an integral
loudspeaker with volume control, or by an earpiece, which is an
optional accessory. The same applies to the Vario sound output.
Short transmitter aerial:
The short 2.4 GHz transmitter aerial is robust, easy to handle,
and does not impinge on the pilot's field of vision.
8.
8.1. Disconnect the transmitter battery ( 2.)
8.2. Screw in the two spacer bolts into the mounting bar
Mount the mounting bar onto the two plastic bolts inside the
radio.
Page 11
I
HFMG4 M-LINK
NSTALLING THE
2.4 GH
RF
Z
MODULE
Washer and Nut M3
plastic bolts