fix: only display PPM multiplier when PPM is used

[3djc]

PPM multiplier is used only on trainer jack input (for history reason when PPM was hardly standardized), but is displayed in all mode. With this change, it is displayed only in master/jack mode

Fixes #5639

[elecpower]

Dumb question time...the Multiplier is stored in general settings (ie radio level) so the value applies to all models however this PR changes to "it is displayed only in master/jack mode" (and edited) which is a model level decision. So to change the radio level value you would have to switch to a model with trainer in master/jack mode.

[3djc]

Not really. It could be done, but likely not worth it. Previously it was always displayed, but used in computations ONLY when model selected master/jack. You could change value and see no change. Now, when you go to radio trainer, you only see it only if it affects the value, and adjusting it leads to the expected result

[philmoz]

I'm not sure I like having a radio setting dependant on a model setting.

I guess this further highlights that the trainer settings in the radio setup should really be model settings.

[3djc]

I disagree with that. Having it model base doesn't make much sense, or at least not more than in radio settings. What we are missing is a trainee settings, where trainer can declare a list of. trainee, each having is own trainer settings:

• Paul
  Use SBUS serial
  CH1:TR1 CH2:TR2 CH3:TR3 CH4:TR4
  Has 100% gain on all axis

• John
  Use DSC PPM
  CH1:TR2 CH2:TR3 CH3:TR1 CH4:TR4
  Has 50% on ail and ele, 30% on rudder

that could be applied to any model.

But that a complete overhaul of the trainer, way outside of the scope if fixing the reported issue

[pfeerick]

As a fix for this particular issue, this does make sense, given the current trainer configuration structure.

There are several issues related to the trainer configuration, so these probably need to be collated and an overhaul of the trainer system as a project. Trims (more customisation - individual trim config, naming, etc) are probably another other area that could do with some TLC. Then there is ... er, you get the picture 🤭