SMALL - Telemetry SMALL - Radio
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Posted by on4mj | Aug 21, 2015 @ 06:55 AM | 1,576 Views
You're probably wondering what this is about.
If you don't know, check this thread first

User manual

Start your media player of choice with the video ready to run.
Start the "sequential timer" program.

Start the video, click the timer window to give it the focus ; then counting is started/stopped with the space bar.

There's a reset button to restart the timer between two runs of the video (write down the results before clicking reset !).
Posted by on4mj | Jun 25, 2015 @ 07:07 AM | 1,095 Views
For quite a long time, now, I have in my "output buffer" an update to the launch height script of Nigel. But I seemed to have a mysterious bug that I could not track down and which caused the Tx to announce completely stupid altitudes.

I've been saying also that I should get back to an older trusted version of the code, and put back my old vario, since I changed it (supposedly for a newer version) at the same time that I changed the code. But, lack of time combined to lazyness, I never actually did it.

I also thought (since I changed the location of the vario in the fuse too) that it could be caused by a sudden depression in the fuse when I launched, and that the script could think that the glider was descending while it was actually climbing at a rate fast enough to suck some air out.

Then I got the Swallow. Maidened it without actually caring about launch heights. But the problem of my older DLG was still in the back of my head, and I decided for the second flight to increase the rate of my logging. Still no script, but I put an SF to announce the altitude when I levelled the plane (the condition which ends my climb/zoom mode). The result was that I had consistent altitude readings, and which seemed more or less credible (with the other glider, it feeled really, really optimistic).

Then I got back and decided to have a look at the log. Then I saw, on almost every climb, something like the sample in this screenshot. Different glider, different vario,...Continue Reading
Posted by on4mj | Jun 07, 2015 @ 03:16 PM | 1,074 Views
Very special conditions today in Anthisnes while I was there :
(1) A lot of wind. Then suddenly it was dead calm. Go to (1).
I don't know how they choose their ballast. It must have been "interesting".

And for those who wonder if a helmet could really be useful, I saw somebody who nearly got beheaded (on a landing !!) today.
Posted by on4mj | Apr 21, 2015 @ 02:46 PM | 1,959 Views
I received my new DLG yesterday. It's the Swallow, by Jonas and Jessica, and you can find everything about it in the dedicated thread.

I started the build today, and as I didn't have much time, I didn't do much.
But, hey, you have to start somewhere, so, I glued the wing bolts in the fuse with 30 min epoxy.

I'll post big pictures so you can see how the finish is.

Needless to say, I'm very happy with it
Posted by on4mj | Dec 05, 2014 @ 03:39 PM | 6,080 Views
My F3K training script for the Taranis, providing timing for all the F3K tasks excepting AULD and poker is now available on RCsettings.

If you have bug reports, improvement suggestions, etc... post them in the comments here, I'll see what I can do.


Updates in 2.03
  • Added variations with a 7 minutes work time in task A & B (at the bottom of the menu).
  • OpenTX 2.1.x compatibility (not tested on the transmitter)


There's a new sound file 'taskb7.wav'.
If you're upgrading from a previous 2.0x release of the script, you can keep your current custom.lua file.
If you're using OpenTX 2.1 (which I do not recommend yet), read the documentation for the installation instructions.

Updates in 2.02
  • Added a quick turnaround practice "task".

Updates in 2.01
  • Fixed a regression introduced in 2.00 which caused the script to crash in several tasks when the plane was still flying at the end of the working time

Special thanks to Cory Shantz for reporting the bug and doing the QA after that.

Quick Fix 7 May 2015

I released 2.00 with the wrong documentation. That's fixed.
Sorry about that.

Updates in 2.00
  • Major refactoring: split the original script in several dynamically loaded files to get rid of all those memory problems
  • Added Task M
  • Correction of a false launch detection problem when the previous task was "Done !&
...Continue Reading
Posted by on4mj | Nov 17, 2014 @ 06:26 AM | 2,637 Views
Work in progress...
Anyway, I need 2.0.13 for this to be fully operational.

And if somebody has an idea of how to handle Poker realistically, please leave a comment. TIA
Posted by on4mj | Oct 29, 2014 @ 09:01 AM | 2,748 Views
((v1.03: the timer voice now works correctly ; THIS REQUIRES THE 2.0.13 FIRMWARE))

The Winterpostal is a friendly F3K competition that you can compete from your backyard.
For more information, see the dedicated web site.

But now, who's gonna come in your backyard to time you ?
Especially in winter ?

So, for those who own a Taranis, the good news is that the radio can do that for you. Although it won't tell you where the lift is !

The November task is the five best flights in a 30 minutes window. Unlimited throws. Max flight time : 300 seconds.

So, here's a little "telemetry" script (it doesn't use telemetry at all) which gives the remaining work time, the current flight time, the best five times, and the total (getting rid of the extra time if you fly more than the max).

There's a little catch-up : the temporary switch is used to detect the start and end of flight. It's probably a little confusing at first : once you land, you must pull the switch and hold it until you launch again.

The other 2-position switch is used to start the work time (when pulled) and end it prematurely if pushed again.

The work time (timer 1) is displayed decrementing, while the flight time (timer 2) is diplayed incrementing. Although, internally, they both are decrementing. I suggest putting voice countdown with minute call on timer 2, you will know where you are in your five minutes.

The script makes use of a few sound files :
  • task1.wav : signals the start of the working
...Continue Reading
Posted by on4mj | Sep 21, 2014 @ 04:42 AM | 2,749 Views
The weather was (almost) ok when I left home.
But to arrive at their field, one needs to cross two streams over the roads. And it's a sad sight. It's pouring cats and dogs. Everybody's inside. I waited for a calmer moment to get out of the car and take a couple of pictures. Didn't even enter to say hello
Et je m'en vais
Au vent mauvais
Qui m'emporte
De, del,
Pareil la
Feuille morte.
- Verlaine -

Posted by on4mj | Sep 09, 2014 @ 02:20 PM | 3,307 Views
This is the second version of this article.
Unfortunately, the first one did not work correctly, so here's an update.


I decided to keep this out of my "Introduction to OpenTx programming" to keep it simple. But, of course, it wouldn't really be complete without a real launch mode.
So, here's one which can be used for real without being too complex.

NB: This post is meant to be an add-on to the aforementioned article.

Launch mode

The idea is that the "launch" flight mode (Fig. 1) is used only to give some up elevator at the start, while disabling the flaps. It's triggered by the pull of the momentary switch. The main difference with the previous one is that there's no fade out.

Adapt the elevator trim to your needs.
Also, if you want some camber during this phase, you can set GVAR1 to "Own value" and set it to what you want (-2 for 1, as I did here as an example).

Climb mode

When the momentary switch is released, a new flight mode is triggered for a few seconds : Climb (Fig. 2). The only purpose of this one is to disable the flaps. There's a quite large fade out, in case your flaps were widely deployed. The control then returns to the flight mode which was selected prior to launch.


Launch is configured with L1 as its switch. Climb is configured with L4 as its switch.
The other logical switches are adapted so that the conditions for each...Continue Reading
Posted by on4mj | Sep 01, 2014 @ 01:27 PM | 6,296 Views
Note: This is an introduction to OpenTX programming. If you're looking for a ready-to-use DLG program, I suggest you have a look there instead.

There seems to be a few myths about the Taranis and OpenTx. And a lot of people seem to struggle to get started with its programming.

The threads on RCgroups, although containing possibly all the required information (redundantly), are *huge* and one can get lost easily.

So, I decided to make the demonstration of how I do it, decomposing my train of thoughts, and to present it in an iterative and incremental way. Hopefully, this will allow most people to get a clearer picture of the process.

The goal here, will be something with application in the real world : the programming of a DLG. It's simple enough, but not necessarily trivial.
  • We have four channel with a flapperon mixing.
  • We definitely want differential on the ailerons.
  • We want flight modes + a special launch mode.
  • We might need some additional mixing to the elevator when the flaps are down.
  • Etc...

I will use OpenTx Companion 2.0.8 for all the demonstration. I make adjustements on the field with the transmitter, but all my initial programming is always done in Companion.

A good way to work is : always get a fresh copy of your TX data in companion before any work on it. When you're done, re-upload the data in the TX. If you forget to download the data before doing adjustments, you will loose all you did in the field.

The firmware/software versions are not really...Continue Reading