Lemon Microbrick Reference Guide
Page 4 of 20
Supply Voltage
Warning: The Lemon Microbrick does not have reverse voltage protection.
Make sure the polarity of the supply is correct!
The Lemon Microbrick is specified to operate on a supply voltage of 3.1v
minimum to 8.5v maximum. In practice this means using a 1s
→
2s LiPo.
All of the onboard components (including the servos) are capable of this
voltage range. However, the two external white servo connectors carry the
full supply voltage and any servos connected to them MUST be capable of
tolerating this. For a 1s application this is not a concern. For a 2s supply
battery it is an issue if you use external servos. For example, you cannot
connect a Spektrum™ linear servo or a
HobbyKing HK5320/5330 servo to the
Microbrick on 2s.
2
Speed Controller and Failsafe
With the onboard 5A
brushed
speed controller, if the Microbrick loses signal the servos will hold their last
position and after a second or so the brushed motor will stop running.
If you are using an external
brushless
speed controller (ESC), then be aware that on loss of signal the Microbrick
stops sending pulses to the ESC. The ESC then knows that the signal is lost, and the motor should stop with slight
delay. Not all small ESCs will do this, and you should test to be sure. For the small models for which this
Microbrick is intended, however, the risk is very small. Moreover, given the exceptional range of the receiver,
loss of signal is highly unlikely.
Basic Setups
Three Channel, Conventional Tail
Default control channels are: 1 = Throttle, 3 = Elevator, 4 = Rudder (TER).
However, you can also set up the Microbrick so that
default control channels are:
1 = Throttle, 2 = Rudder, 3 = Elevator (TRE).
This means that the Aileron stick controls the Rudder.
Many people prefer this for three-channel models. See
page 13 for instructions on how to do this.
Four Channel with Single Aileron Channel
For 4-channel models with single aileron channel, plug the
aileron servo or two servos on a Y-lead, into the right-
hand white 3 pin JST-SH 1.00mm connector (see photo at
right). Choose Normal Wing in the Spektrum Aircraft Type
menu.
2
The HobbyKing servos are rated to 4.8v but people have found that they work up to 5v satisfactorily. They can be
used in a 2s brushless setup where the speed controller has a 5v BEC supplying the Microbrick but must not be used
on a direct 2s (8.4v) supply. Lemon will be stocking a version of this servo under their own name.
