Highlight and select MASTER and the display will 
switch to SLAVE. A message appears instructing to 
Connect DSC & POWER off. Make sure the transmitter 
power switch is in the Off position and the trainer cord is 
connected between the 2 transmitters.
If the master system is an XP9303, X9303 2.4, X9503 2.4, 
or 12X and the individual channels are not selected in the 
master system’s trainer function, leave the slave system’s 
The X9503 2.4 contains a Timer System that contains 
two timers. One is an integrated timer that keeps track 
of total time that the transmitter has been on for the 
model and appears on the Main display. The other timer 
can be configured as either a Countdown timer or as a 
Stopwatch. This timer also appears on the Main display 
when active and can be started, stopped and reset from 
the Main display. It is a good idea to use the Countdown 
timer as a reminder that it is time to land so as not to run 
out of fuel.
If using the Countdown timer, an Auto Start function is 
available that starts the timer when the throttle is raised 
over 20% the first time after the transmitter is turned on.
1. To configure the timer as a Countdown timer highlight 
and select Timer in the FUNC.LIST to obtain the 
Timer display.
Highlight and select INH under TIMER then select 
DOWN-T. Use the Selector to set the countdown start 
time. Once the timer is set, TIM will appear on the Main 
display in the lower left corner. Pressing the button next to 
TIM on the Main display starts and stops the timer while 
pressing the button next to CLR resets the timer to the 
programmed value.
2. To Reset the Integrated Timer, highlight and select the 
time under INTEG-T and Push[CLR]=0:00 appears 
on the display. Press the CLR button to the left of the 
display to reset the Integrated timer. If the momentary 
button or switch is not used for another function, it can 
also be used to start and stop the timer.
trainer function in the default MASTER setting.  In this 
case, both the master and the slave systems must be fully 
programmed and set up to fly the model including all 
servo reversing, travel adjust, program mixes and all other 
necessary programming. 
The X9503 2.4 is now ready to be used as the Slave or 
student transmitter.
3.  If the Auto Start function is desired which starts the 
timer by the throttle stick, select INH next to STICK and 
select this to ACT. With this set to ACT, the Auto Start 
function will start the timer when the throttle stick is 
raised above 20%.