Telemetry Value to Percentage


Featured functions

  • Two separate calculators with identical functions
  • Convert (almost) any telemetry sensor’s value to percentage
  • User definable sensor value-range
  • User definable decimals
  • Possibility to use 0-100% or 100-0%
  • Creates Lua control (freely usable switch)
  • Enable – disable alarms
  • Lua Control has freely definable alarm-point
  • Alarm-point is definable to ascending or descending
  • Creates telemetry window for main screen (One per sensor)
  • Telemetry window label is user-definable
  • Single and double telemetry-windows available
  • Possibility to show sensor-value in telemetry window
  • Available for all transmitters with Lua-capable firmware
  • Possibility to use receiver-voltages as sensor


  • Show 0% when 480ml fuel is used
  • Alarm when 10% fuel left
  • Show 100% when 3000mAh capacity is used
  • Alarm when 90% capacity is used
  • Use cell-voltage as basis for empty battery
  • See receiver voltage as percentage


In short: Copy the (or .lua, the .lc is memory-optimized) file from github here to your transmitters Apps-folder, copy the RCT-Perc.jsn file to Apps/Lang-folder on your transmitter. Head on to “Applications” -> “User applications” and add the app. Guide on installation of Lua-apps available here if you need some more in-depth guide.

Setting up and using “Percentage Display”

After opening the application from “Application” -> “Percentage Display” you are greeted with settings for the first screen. Settings are the same for 14/16 and 24 transmitters. Only difference is that 24 has two percentage-windows.

Setting up is basically the same way as with any other function in Jeti. First let’s create a suitable label for the value, let’s say we want to make a “Battery left” indicator, where we get 0% when all the mAh is consumed. So, change the label from the default:

After that it is time to select the sensor. From the “Select sensor” menu choose (for example) the altitude-sensor and set rest of the values to your liking:

Sensor low value is the sensors value where you want to have 0%, sensor high value is the sensors value where you want to have 100% in display. What this means is that you can choose if you want percentage to go 0-100% OR 100-0% when telemetry sensors value increases or decreases. What this means is total freedom in usage.

You can also use Percentage-application in more versatile way. It is now possible to choose sensor- and alarm-values with up to three decimals.

Enabling alarm gives you possibility to use the application control (switch C01) as alarm for percentage value. If Low alarm is DISABLED alarm will activate when percentage value gets OVER the value set in Alarm point value. If on the other hand Low alarm is ENABLED the alarm will go off when percentage value goes UNDER the value set in Alarm point value. Alarm is enabled automatically if “Alarm Point Value” is changed to something else than zero.

Using the percentage alarm for example in voice announcements is easy, just choose the corrsponding “PercentageCtrl” switch from “Apps” in switch selection dialog:


Application also offers a possibility to get the percentage to main screen. Simply go to your “Timers/Sensors” -> “Displayed Telemetry” and choose the telemetry with the name you gave as label earlier:


This will give you a double-size telemetry windows on your main screen in a position of your choosing:

Window shows “-%” if transmitter does not get any telemetry, this function is on par with the built-in displays of Jeti transmitter. If no sensor is configured the windows shows 0%

Version history

  • 1.0 Original version
  • 1.1 Housekeeping, moved to “one app”
  • 1.2 Bugfixes
  • 1.3 Fix of persistent save, removed from “one app” to own application
  • 1.4 Added second sensor and telemetry window
  • 1.5 Performance fix, loop is over 300% faster now
  • 1.6 Fixed telemetry window if no model powered
  • 1.7 Fixed reset if user removes sensor from settings
  • 1.8 Added multi-language, languages available EN, DE
  • 1.9 Fixed: Error when used together with all other apps, Added French translation – Courtesy of Daniem Memin
  • 2.0 Added possibility to select decimals 0 to 3
  • 2.1 Corrected main-screen bug – clearer interface (Alarm)
  • 2.2 Added Spanish translation from César Casado
  • 2.3 Added Italian translations from Fabrizio Zaini
  • 2.4 Memory improvements
  • 2.5 Big memory improvements, separate version for 14/16, streamlined usage, possibility to use receiver voltages as sensors


Some rules do of course apply!

  • Never use LUA to control a function that would take the model down if misbehaving!
  • Always, always test the function thoroughly!
  • If you do not know, then don’t!
  • RC-Thoughts or myself is NOT responsible for anything this application does
  • Applications are free to use (MIT-license) and linking to this page is encouraged!