Dsmx – Spektrum SPMAR12020 User Manual

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DSMX

Spektrum launched the 2.4GHz RC revolution with its DSM2™ technology. Since

then, millions of hobbyists the world over have come to embrace 2.4 as the way

to fly. Spektrum leads the way yet again with DSMX—the world’s first wideband,

frequency-agile 2.4GHz signal protocol.
How Does DSMX Work?

It’s a crowded 2.4GHz world out there and every 2.4GHz system faces the same

challenges. DSMX better equips you for these challenges by combining the supe-

rior data capacity and interference resistance of a wideband signal (like that used in

DSM2) with the agility of frequency shifts.

Compared to the wideband signal of DSMX, the narrow band signal of other

frequency hopping 2.4 transmitters is more likely to suffer data loss in the event of

on-channel interference. Think of it as a river vs. a stream. It takes more interferen-

ce to dam a river than it does a stream.
As more and more 2.4 transmitters vie for the same number of available channels,

there is more interference and more of a risk for data loss. By adding the agility of

frequency shifts to the superior interference resistance of a wideband signal, DSMX

is far less likely to suffer significant data loss from on-channel interference. The

result is quicker connection times and superior response in even the most crowded

2.4GHz environment.
DSMX Operational Differences

DSMX transmitters and receivers function nearly identically to Spektrum DSM2

systems. Binding, setting the failsafe, recording flight log data, as well as general

use of the system is no different than using any current Spektrum system.

Following are the operational differences:

Brownout Detection - Not Available on DSMX Receivers DSM2 receivers feature

Brownout Detection that flashes the receiver’s LED if a power interruption occurs.

While DSMX receivers have QuickConnect

™

technology and recover instantly from

a power interruption, the architecture of DSMX prevents Brownout Detection when

operating in DSMX mode.

Flight Log Recording-Fades Higher than DSM2

Note that DSMX hops through the band while DSM2 finds two quiet channels and

remains on those channels. Consequently because DSMX operates on quiet and

noisy channels, it’s common to have more Antenna Fades than when using DSM2,

when used in busy 2.4GHz environments. When taking flight log data readings, the

Frames and Hold Data are important and should be used a reference while Fades

are insignificant due to the nature of frequency hopping. A 10-minute flight will

typically result in less than 50 Frame Losses and no Holds.

Just How Good is DSMX?

In multiple tests, 100 DSMX systems were operated simultaneously for extended

periods of time. During these tests each of the 100 systems was monitored in flight

and on the ground. In every test not a single case of RF link loss, latency increase

or control degradation was experienced or recorded.