Motor Suppression; Receiver Aerial - GRAUPNER XS-6 FM RACE synthesizer Operating Manual

Appendix
Supplementary notes

Receiver aerial

The receiver aerial is attached permanently to the
receiver, and is about 100 cm long.
The aerial should be deployed in as straight a line as
possible, and as far away as possible from electric
motors, servos, metal pushrods and high-current leads.
In model boats the receiving system should be installed
in such a way that the receiver and the aerial are as far
away as possible from electric drive motors, high-current
cables and metal parts.
For model boats a vertical whip with a free length of 80 -
100 cm is preferable to any other type of aerial.
Whip aerials have also proved excellent in model cars.
As an exception to the rule, a shorter aerial may be used
in a model car since the range required is relatively short.
Installing pushrods and linkages
The basic rule is that all linkages must be unobstructed
and free-moving.
Stiff pushrods and control systems cause higher currents
to flow, thereby reducing running times and adversely
affecting accuracy of control. It is especially important
that all servo output arms are free to move to the full
extent of their travel in both directions without being
mechanically obstructed at any point.
Any areas of the model through which pushrods pass
must be checked carefully, to ensure that they do not
foul the linkage. The same applies to hinged components.
It is particularly important to check that the throttle system
fulfils this requirement.
The "full throttle" setting must be determined by the stick
position, not by the mechanical end-stop of the throttle
system.
If this is not the case, the servo will be under full load
almost constantly when the model is running; it will then
draw a heavy current and may burn out.
For the same reason the idle setting must also be defined
electrically, i.e. through the stick position, and not
mechanically through the throttle system end-stop.
Suppressing electric motors
All conventional electric motors generate sparks between
commutator and brushes, and the sparking causes
interference to a greater or lesser extent to the radio
control system. For this reason all electric motors in the
model must be effectively suppressed if the radio system
is to work properly.
In electric-powered model boats the motors must
therefore be suppressed carefully.
Suppressor filters are reasonably effective at suppressing
this type of interference, and should always be used in
any model powered by an electric motor and controlled
by radio.
Wherever possible suppressor filters should to fitted as
close as possible to the drive motor, and the connecting
leads from the terminals to the motor's earth connection
should be as short as you can possibly make them (max.
20 mm). Each electric drive motor must be suppressed
separately, with its own suppressor filter.
Order No. 3588
Minimum suppression
Order No. 3361 (max. 18A)
Order No. 3362 (max. 36A)
Suppression using suppressor filter
Please refer to the main GRAUPNER FS catalogue for
details of suppressor components and suppressor filters.
Order No. 3584
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