Turnigy 9x with 2 modules

[amxcs]

I have several receivers at 72mhz and I want to use it with one transmitter.
I tested with the FM module and everything is fine.

https://www.youtube.com/watch?v=0huUQ1nFEfg&feature=youtu.be

The original antenna will not be used. The multiprotocol module has an antenna. I can put the telescopic antenna from Hitec.


1. Can I insert the FM module into the transmitter if I find a place and switch between two modules? Switch only ppm and V+?



2. 350uS and PPM FrLen 22.5mSec do they need to change?

Thanks!

[amxcs]

[amxcs]

Today I wanted to test the transmitter before a flight.
At 72MHz, when I press the trim several times quickly, the transmitter stops working - voltage anomalies and nothing works. After a restart, everything is fine until I press the trim again.




Thus the transmitter is unusable. If I do not find the problem I will have to remove the module.

EDIT: Do I need a PPM inverter like this adapter? And what does it do?

[MikeB]

I think your problem with the trim switches is the one discussed here: https://openrcforums.com/forum/viewtopi ... =95&t=3594.
Basically, there is a design flaw in the 9X for the horizontal trim switches, which means some radios suffer a problem when using the horizontal trim switches.
If you don't have the problem when using the vertical trim switches, but the horizontal trim switches cause the problem,then you need to modify the horizontal trim switch wiring.

The adapter in your edit is to allow a futaba/hitec module to fit in a JR style module bay.

Mike

[bob195558]

Also see here about "9x Radio Rebooting Problem Horizontal Trims Digital Ground Fix"
https://openrcforums.com/forum/viewtopi ... 120#p69475

[amxcs]

Done, tested and works well on 72Mhz and 2.4Ghz

The adapter in your edit is to allow a futaba/hitec module to fit in a JR style module bay.

Yes, but what is the inverter for? I have connected the PPM signal directly.

[MikeB]

It inverts the CPPM signal from the radio to the module. Since er9x may output the signal with either polarity it is totally unnecessary!

Mike

[amxcs]

Thanks!

I have 1 more problem.
With the FM module it shows the wrong battery voltage by 1V more than with the original module. It is measured with a multimeter.
The voltage is calibrated with the original module.
Can I do a voltage calibration on a new model or is it for all models.

[amxcs]

Unfortunately, the calibration is for all models.
I don't know why with different modules it shows different voltage. The difference is not 0.1-0.2V to ignore it, but 1 volt.

[Kilrah]

Most likely the 72MHz RF screwing up the measurement.