ROBBE RASST Systems Bedienungsanleitung Seite 19

Additional information on other RC components
The above recommendations are beneficial not only for receivers, but
also for other electronic components.
• Heat sinks in speed controllers that have already been subjected
to thermal load do not dissipate heat as effectively and are more
susceptible to overload in operation.
• The energy output of LiPo batteries deteriorates by approx. (10-
12%) with increased temperatures above approx. 45°C, thus
reducing the performance capability of your model.
• The power output of servos is also partially reduced at high tem-
peratures - the higher the temperature of the motor winding, the
poorer the efficiency. That means, at temperatures of around 55 C,
the power output can be up to 20% less than when cold. This limit
is quickly reached due to the high self-generated heat caused by
the servo motor.
General information on 2.4 GHz RC systems
• In general, the range of the 2.4 GHz FASST system is greater
than that found with 35 MHz systems. The range is approx. 2000
metres close to the ground and more than 3000 metres in the air.
The weather conditions and obstacles that reduce range as descri-
bed below, do not necessarily impair operation but rather simply
affect the reserves.
• Larger obstacles between transmitters and receivers can dampen
or block signals.
• When close to the ground, damping of the transmission signal is
greater than is the case with 35 MHz systems. The range close to
the ground can be reduced on foggy/ misty days and /or when the
ground is wet.
• The range can be greatly reduced when a model is close to the
ground and an obstruction (person, vehicle, object, etc.) moves
between the transmitter and receiver.
• The propagation of 2.4 GHz signals is virtually linear. This means
it is necessary to always keep visual contact with the model.
• The FASST receivers, R607, R617, R608, R6008 and R6014 are
fitted with a Dual Antenna Diversity System with 2 aerials and input
stages. This system constantly monitors the signal strength on
both aerials and switches instantly and seamlessly to the one with
the strongest signal strength.
• When the two aerials are aranged at an angle of 90° with respect
to each other, the usual positional dependency found with only one
aerial is greatly improved, thus considerably enhancing reception.
• The PRE-VISON software permanently scans the input signal and
corrects any errors if required.
Observe the following information on aerial installation to achieve
optimum signal reception:
• Both aerials should be installed fully extended.
• The angle of the aerials should be approximately 90°in relation to
each other.
• Large models often have larger metal parts which could dampen
RF reception. In such cases, position the aerial to the left and right.
• The aerials should not be installed parallel to, and at a minimum
distance of 1.5 ... 2 cm from:
• Metal, carbon, cables, bowden cable, wire controls, carbon push
rods, carbon rovings, etc.
• Current-carrying (live) controller or motor cables
• Spark plugs, spark plug heaters
• Locations subject to static charge such as toothed drive belts, tur-
bine, etc.
• Lead aerial the shortest way out of fuselages with shielding mate-
rials (carbon, metal, etc.)
• Do not secure the ends of the aerials either on the inside or out-
side of electrically conductive materials (metal, carbon)
• This does not apply to the coaxial cable but only to the end area of
the aerial.
• When installing the coaxial cable avoid tight radii and kinks.
• Protect receivers from the effects of moisture.
Notes on installing 2.4 GHz FASST receivers:
• Use a low-resistance NC or NiMH battery as the power supply.
• Clocked BEC systems for supplying power must be sufficiently
sized in terms of specification. If the voltage drops below a value
of 3.8 Volt when under load, the receiver must reset and restart,
involving signal loss for approx. 2-3 seconds. To prevent this hap-
pening, the receiver should be fitted with RX capacitors which
bridge temporary
voltage fluctuations. (Rx capacitor 1800 μF No F 1621 or 22 000
μF No F1622)
• Thanks to their high intermediate frequency of 800 MHz, 2.4 GHz
FASSTreceivers are relatively immune from electrosmog (such
as metal-to metal interefrence pulses, RF radiation, static charge,
etc.) as they only have a low amplitude at frequencies above 300-
400 MHz. If using a device with a known potential of interference,
it may be prudent to install an interference suppresion filter No F
1413 to shield the receiver from the interefrence source. Whether
the use of such a filter is necessary will be found during range
testing.
Corresponding precautions should be taken on the model to
avoid strong static charge: Helicopter:
• Connect an earthing strap between the tail boom and chassis.
If required, fit a „copper brush" on toothed belt drives to remove
static charge from the belt. If necessary, electrically connect the
toohed belt pullies to the chassis.
• It is often necessary to connect the tail boom to the motor casing
on electric helicopters.
• The use of carbon fibre-reinforced/glass fibre-reinforced blades as
well as a carbon fibre-reinforced tail boom can generate conside-
rable static charge particularly at high speeds and low air humidity.
To avoid this happening, a conductive connection should be made
from the tail rotor gerbox up to the main rotor shaft.
An electrical connection exists in main rotor shafts. Also the use of
Anti-static sprays has proven effective.
Turbines:
To avoid static charge, connect an earthing strap to the turbine
shield.
• High static charge (approx. 40,000 Volt) often builds up in fast
jet models made from glass fibre-reinforced materials due to the
high speed (especially in low humidity conditiions). Glass fibre-
reinforced parts, larger than about 10 cm², should therefore be
connected conductively to each other.
• Connections led outwards through the fuselage (tank connection,
etc.) should also be connected conductively to each other to avoid
static charge. Static charge over the tank hose can cause shut-off
valves to operate .
• Tyres on the undercarriage can also generate static charge and
should therefore be fitted with copper brushes.
Range test:
• Before starting up a new model or a new receiver or using a
new receiver, it is recommended to carry out a range test. The
model should not be placed directly on the ground but raised by
approxiametly 1-1.5 m above the ground. Use a plastic or woo-