MC24 replacement of stick assembly
Through a little mistake I damaged the aileron trim of my MC24. I already know this transmitter by heart, so it is not a big deal to replace the stick assembly.
After a short email conversation with the friendly Graupner support, a new stick assembly was on the way to me, and after succesful change, here it is the manual for it. When you keep some small things in mind, every model builder can do that on his own, but you need to take care of, that it is only possible with old software versions to get in the secret menu to calibrate the sticks after the change. Because this is necessary, you should look at first if you can enter the menu, if not, you need to send the transmitter to Graupner for the change.
After a short email conversation with the friendly Graupner support, a new stick assembly was on the way to me, and after succesful change, here it is the manual for it. When you keep some small things in mind, every model builder can do that on his own, but you need to take care of, that it is only possible with old software versions to get in the secret menu to calibrate the sticks after the change. Because this is necessary, you should look at first if you can enter the menu, if not, you need to send the transmitter to Graupner for the change.
Change of the stick assembly:
At first step, you should build a working pad. I used a quadratic foam which has nearly the meassurements of the transmitter and cut two holes for the sticks so that the transmitter is lying on the case and not on the sticks. When working on a transmitter, always take care that you are grounded, so touch a radiator or something similar before starting.
Remove the back casing and unplug the battery. If you have switches in your sticks, you should also unpleg them now.
As next, you should photograph the proportinal inputs in which order they are attached to the board and then disconnect them. Here you can see the oem order.
Remove both screws which are connection the side plates with the battery mounting:
Turn the transmitter upside down and remoce the sticks through just pulling them straight out. Also remove the small screws which connect the side plates with the case. There are five screws, the laso one is hidden where the clip for the strap is located.
As next, you need to remove the small plate where the sliders are located. Just remove the four srews which are good to see:
You can see now two plugs where the stick assemblies are connected to the mainboard. unplug the left one for the left assembly and the right one for the right assembly:
Th easiest you are now putting up the transmitter in a vertical position to remove the four screws which are holding the cover and the stick assembly in place. here it is helpful to support the transmitter with your other hand from the back side:
Now you are finished, the stick assembly is removed and putting all together again can be done in reverse direction:
Calibration of the new stick assembly:
After changing the stick assembly, it is necessary to calibrate the new one. Of course, the potis are wear parts, according to their treatment they will last about five to fifteen years. So it makes sense, to do a calibration from time to time. it is very important that the transmitter is set to mode 1, otherwise the values will be stored false. I saved one fixed wing model as "calibration" with mode 1 without any additional set up, so you can go there into the servomonitor and you will see immediately if the sticks are still correct. In neutral position, it must show 0 for channel 1 to 4 and at the end points it should show -100 respectively +100.
To calibrate the sticks, follow this procedere:
To calibrate the sticks, follow this procedere:
Go into the secret menu through holding down the rotary selecter and press two times fast at the same time "Start" and "Stop":
As first step, we will save the neutral position of the sticks and the trim, for that, press both buttons under "NEUT." at the same time. neutralize the sticks and the trimand then press "STO" to save. The sticks and the trim can be saved seperately.
In the darker fields you can see now the new position and in the fields behind them the offset value.
With a press on the enter button you get forward to the gain menu where the maximum values for each stick will be saved:
Trough moving the stick to the end position, the new maximum values will be stored automaticly. it looks very rough, but don't bother, the calibration is done in full resolution. You are not forced to calibrate all sticks, you can also calibrate only one direction of one stick. if you don't move one stick, there will also no new values stored. With a press on enter, the calibration will be finished.
You will find yourself now in the last menu where some other calibrations can be done.
Far on the left you can see the voltage of the back up LiIo battery and with + and - you can correct that. Then there will be shown the voltage of the "normal" battery which you could also correct.
In the middle you can adjust the limit for the battery warning. Originaly it is set up at 9,3V for 8 NiMh cells, if you want to use a LiPo intead of NiMh you can change the limit for the alarm here.
I haven't found out whats behind the abbreviation "cont." is hiding, but with the "meter" you can adjust the position of the needle in the voltage display which is located under the antenna.
If you press now enter you will leave the secret menu.
Now you can go into the servomonitor and check if the calibration was done correct for all channels.