Spektrum SPMAR9010 User Manual

Page 14

band looking for the previously stored GUID. When it locates the specific GUID

code and confirms uncorrupted repeatable packet information, the system

connects and normal operation takes place. Typically this takes 2 to 6 seconds.
Q: Sometimes the system takes longer to connect and sometimes it

doesn’t connect at all?
A: In order for the system to connect (after the receiver is bound) the receiver

must receive a large number of consecutive uninterrupted perfect packets

from the transmitter in order to connect. This process is purposely critical of

the environment ensuring that it’s safe to fly when the system does connect. If

the transmitter is too close to the receiver (less that 4 ft.) or if the transmitter is

located near metal objects (metal TX case, the bed of a truck, the top of a metal

work bench, etc.) connection will take longer and in some cases connection

will not occur as the system is receiving reflected 2.4GHz energy from itself

and is interpreting this as unfriendly noise. Moving the system away from metal

objects or moving the transmitter away from the receiver and powering the

system again will cause a connection to occur. This only happens during the

initial connection. Once connected the system is locked in and should a loss

of signal occur (failsafe) the system connects immediately (4ms) when

signal is regained.
Q: I’ve heard that the DSM system is less tolerant of low voltage. Is the

correct?
A: All DSM receivers have an operational voltage range of 3.5 to 9.6 volts. With

most systems this is not a problem as in fact most servos cease to operate at

around 3.8 volts. When using multiple high-current draw servos with a single

or inadequate battery/power source, heavy momentary loads can cause the

voltage to dip below this 3.5-volt threshold thus causing the entire system

(servos and receiver) to brown out. When the voltage drops below the low

voltage threshold (3.5 volts), the DSM receiver must reboot (go through the

startup process of scanning the band and finding the transmitter) and this can

take several seconds. Please read the receiver power requirement section as

this explains how to test for and prevent this occurrence.
Q: Sometimes my receiver loses its bind and won’t connect requiring

rebinding. What happens if the bind is lost in flight?
A: The receiver will never lose its bind unless it’s instructed to. It’s important

to understand that during the binding process the receiver not only learns the

GUID (code) of the transmitter but the transmitter learns and stores the type

of receiver that it’s bound to. If the transmitter is placed into bind mode, the

transmitter looks for the binding protocol signal from a receiver. If no signal is

present, the transmitter no longer has the correct information to connect to a

specific receiver and in essence the transmitter has been “unbound” from the

receiver. We’ve had several DX7 customers that use transmitter stands or trays

that unknowingly depress the bind button and the system is then turned on

losing the necessary information to allow the connection to take place. We’ve

also had DX7 customers that didn’t fully understand the range test process

and pushed the bind button before turning on the transmitter also causing the

system to “lose its bind.”