Spektrum DX18 SPM18000 User Manual

SPEKTRUM DX18 • TRANSMITTER INSTRUCTION MANUAL

NOTICE: The DSMX DX18 is compatible with all current Spe-
ktrum DSM2 and DSMX aircraft receivers, but NOT compatible 
with the original DSM AR6000 receiver.

Set up and operate a model so power to the receiver is NEVER 
interrupted while fl ying. This is especially critical on giant-scale 
models that use several high-torque or high-current servos. 
Power systems unable to provide minimum receiver voltage 
in fl ight are the number-one cause of in-fl ight failures. Some 
components that cause a receiver to have too little power supply 
include: 

• Receiver battery 

(number of cells, capacity, cell type, state of charge)

• Switch harness
• Battery leads
•  Regulator (where used), 
•  Power bus (where used)

A Spektrum receiver’s minimum operational voltage is 3.5 volts. 
This battery charge capacity compensates for discharge during 
fl ight or for fl ight loads larger than ground test loads.

We recommend that you DO NOT fl y a model 

with battery charges at less than 5.3-volts.

1. When setting up large or complex aircraft with multiple high-

torque servos, use a current and voltmeter (HAN172). Plug 
the voltmeter in an open channel port in the receiver, and 
with the system on, load the control surfaces on your aircraft 
by applying pressure with your hand. Monitor the current as 
you load control surfaces. The voltage should remain above 
4.8 volts even when all servos are heavily loaded.

2. With the current meter inline with the receiver battery lead, 

load control surfaces while monitoring the current. The 
maximum continuous recommended current for a single 
heavy-duty servo/battery lead is 3 amps. Short-duration cur-
rent spikes of up to 5 amps are acceptable. If your system 
draws more than these currents, you need to use multiple 
packs of the same capacity with multiple switches and 
multiple leads plugged into the receiver.

3. If using a regulator, perform tests for a 5-minute period. A 

regulator may provide adequate short-term power, but this 
tests its ability to maintain voltage at signifi cant power levels 
over time.

4. For really large aircraft or complex models, multiple battery 

packs with multiple switch harnesses are necessary. No 
matter what power systems you choose, always carry out 
test #1. Make sure the receiver is constantly provided with 
4.8 volts or more under all conditions.

 When charging any brand of NiMH battery 

pack, make sure the battery is fully charged. Due to the 

nature of peak charges and variations in charging rates, heat 
development, and cell types–the capacity reading of a battery 
charged on a fast peak charger may only reach 80% of its 
nominal value. Use a charger that displays total charge capacity. 
Note the number of mAh put into a discharged pack to verify the 
charge is at full capacity.

You can perform mode changes in the System Settings screen. 
However, if you desire to change modes between 1 and 2 or 
between 3 and 4, please contact Horizon Hobby for assistance 
due to requirements for changing gimbals.

Adjust stick tension using the screws on the stick gimbals 
through holes in the back of the transmitter. 

1. Remove rubber plugs from holes marked with a vertical 

arrow or a horizontal arrow. 

2. Turn the screws in these holes a small amount using a small 

Phillips screwdriver to adjust tension on the vertical and 
horizontal gimbals. 

NOTICE: Always do a test of stick tension while turning these 
screws to ensure stick tension is not too loose or too tight. 
Tightening a screw too much can damage a spring. Loosening a 
screw too much can let a spring fall off and cause short-circuit 
in the transmitter.

 Always power off the transmitter, disconnect 

and remove the battery before adjusting stick tension or 

friction straps. Not doing so could result in property damage or 
injury.

1. Adjust control stick length using a 2mm Allen wrench. 
2. Turn the setscrew in the stick counterclockwise to loosen it. 

Make the stick shorter by turning it clockwise or longer by 
turn ing it counterclockwise. 

3. After adjustment of stick length, tighten the setscrew.