VAR Mixers and Aileron Differential

 Any value entry box in ETHOS with a square in the upper left can have 3 special input options assigned, Minimum, Maximum and 'Use a Source'

Use a source is incredibly powerful, it can mix pretty much anything that you can get a usable value out have. This allows adjustable differential from a trimmer, slider or pot, or multiple selectable values from a VAR mix.

I've seen two requests for multiple selectable Differential values with 2 different use cases, the first was on low rates only, the second wanted independent settings for left and right aileron. In the first case, a simple switch designation works, but the second requires use of a logical switch to select which direction is active. 

In either case, the VAR mix is pretty much identical. You do the following:

1. Setup a VAR Mix, name it meaningfully ('Ail Diff' works), assign the Output to a high channel and accept the renaming of the channel (in this example, it will be ch64)

Your default weight is whatever value you want to be the differential value when the selector (logical switch or physical switch) is inactive.
Add a weight, select your switch, add the value you want when the selector is active.

You can of course have multiple options in the list, VAR mixes are prioritized, so the top value whose selector is true will be the value sent to the channel.

Finally, go to the aileron mix, make sure you have at least 2 outputs selected (otherwise Differential won't do anything), scroll down to Differential. Long-press the value field and select 'Use a Source'. Set the Source to Channels->CH64 (Ail Diff) or whatever channel you used for your VAR Mix output. 

Battery Connector Soup

 (Originally Published July 22, 2022)

Battery connectors are an enduring frustration for many. BnF type aircraft come with a variety of connectors depending on the source, batteries and chargers are the same.

For the last couple of years, I've been standardizing my fleet on XT series connectors. However I'm coming to the realization that this doesn't work as well as I'd like overall. I still mostly have electrics even with my increasing interest in glow, and I expect I'll continue to fly electrics long-term, at least for smaller stuff. I may or may not convert my 2 60-ish sized electrics to glow at some point.

All my small stuff except actual UMX's is on XT30. This works fine.
My larger 3S stuff is a mix of XT60 and iC3 batteries and iC3 ESC connectors (all Avian ESC's)
My 4S stuff is a mix of iC3 and XT60 at the aircraft.

The challenge is that I don't buy batteries mail-order, only in my LHS's. I'm having trouble finding mid-sized 4S packs (larger than 2200 and smaller than 5000's) from brands other than Spektrum locally. 

The takeaway? I'm going to standardize on iC3 for larger 3S, I only really need 4x 2200's right now and have 2 iC3 ones, so I'll get 2 more and retire all the other old batteries via Swap meet.

For 4S, I'm going to start standardizing on iC3 as well, but I'll convert my current batteries to iC3 as they're newer, higher performance batteries.

On the charger side, I'll look at getting an S2100 or S2200, then maybe replacing my iSDT D2mII with a second S2x00. I'll also get the Spektrum battery checker to supplement my iSDT one (I'll keep the iSDT for the SBus/PWM checker feature, the Spektrum replaces that with a Servo test feature that's equally useful) 

ETHOS Model Pictures - Pre- 1.2.6 Gotchas

 A couple notes on model pictures for ETHOS for old firmware or X18/X-Lite

1. The path on SD/NAND has changed as of 1.2.6, it's now /bitmaps/models and you will need to rename it from /bitmaps/user which was the path before 1.2.6. If your model pics all disappeared after updating, this is the issue. This is common to the X18 and X20 only, XE and X-Lite do not come with the old firmware and so do not have this issue unless you are cloning content off a radio on old firmware

2. The X18 will rescale BMP files, it won't do the same with JPEG or PNG. You need to resize manually to 188x160 if using JPEG or PNG.

Flap to Elevator Compensation in ETHOS

The Flap to Elevator compensation mix causes a lot of grief in ETHOS, for one simple reason.

If you use the Flaps control as your source and you apply any sort of slow up/down on the flaps, your compensation reacts faster than your flaps do and you cannot apply a matches slow in the compensation mix.

The solution is equally easy thankfully.

Don't use the Flaps control (switch/analog input), use the flaps channel as your source.

Then the compensation mix will follow what is being sent by the Flaps mix. It will also follow any other mixing you do to flaps though, so be sure to disable the compensation mix in any situation where full-span ailerons are active.


One caveat here, DON'T set your flap endpoints in the Flaps mix, set them in Outputs. Using Outputs gives you a few things.

1. It's much easier to balance multiple channels by using a 3-point curve on your reference channel (the one with the more limited physical throw if such exists) and either a 3 point or a 5 point curve on the other channel(s). Use a 3 point for the matched channels if using a 3-pos, a 5 point if using an analog input (like spoiler stick for a sailplane).

2. This lets you have a normal set of flaps settings, then an 'over flap' if you have an aircraft which has tons of flap throw, but doesn't normally need this. I will be using this on my Valiant 10cc, which has ~80 degrees of flap throw but doesn't need more than 60 degrees when landing, the extra throw will be tied to an Airbrake mode for controlling speed when diving.