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Archive for November, 2016
Posted by Miami Mike | Nov 24, 2016 @ 07:34 PM | 17,300 Views
Using Logic Symbols and Digital Electronic Schematic Diagrams as An Aid to Understanding and Designing Logical Switch Setups

I've found that it can be useful to draw schematic diagrams of equivalent digital electronic circuits for logical switch setups that I'm designing or analyzing.

For a fairly simple example, here's the code that activates and deactivates the CAL (Calibrate) mode in Mike Shellim's F3J/TD setups:

L3 is the output. When L3 is true the radio is in CAL mode (Flight Mode 1).

Here's what it looks like when translated into a schematic diagram:

To enter CAL mode the stick is held in the lower-left corner (L5 is true) and the spring-loaded SH switch is pulled (SH↓). To exit CAL mode, SH is pulled (SH↓) with the stick not in the lower-left corner.

An interesting fact about this arrangement is that the combination of L2 and L3 serve virtually the same function as a sticky. This is much easier to see in the schematic diagram than in the radio programming.

So why not use a sticky instead and save a logical switch?

Here's an alternate "circuit":

...Continue Reading
Posted by Miami Mike | Nov 15, 2016 @ 11:00 PM | 17,425 Views
Getting The Most Out Of Your Trim Switches

A Continuation of Taranis: Conserving Switches, Part 1

When you're flying a full-house glider you need your elevator and aileron trim switches, but you probably have no need for throttle or rudder trims. That means those switches are free for other purposes, and there are plenty of useful things they can do.

When a trim switch is set to Own Trim in a particular flight mode, a trim switch adjustment that's made while in that flight mode will store a unique value in memory that applies only while in that flight mode. And through a mix, the trim switch can have a unique function that's also only active in that flight mode. You can see an example of a trim switch serving two different functions in Mike Shellim's F3J/TD setup, in the mixes for CH20 and CH22:
CH20 (Snap)
 Ele Weight(+100%) Flight mode(T3-speed) NoTrim Function(x<0) [Ele]
*= TrmT Weight(-50%) Offset(50%) [TrmT]

CH22 (SpComp)
 CH16 Weight(GV7) Flight mode(Landing) Curve(2) [Spoilr]
*= TrmT Weight(+50%) Offset(50%) [CompAdj]
Here, TrmT (the throttle trim switch) adjusts snap flaps while in T3-speed mode, and adjusts elevator compensation while in Landing mode.

But you can go way beyond that.

Here are Mike Shellim's aileron camber and flap camber mixes from his Version 3, F3J300_X:
CH10 (AilCm) 
MAX Weight(GV3) Flight modes(Launch, Zoom, KAPOW, T1-thermal, T3-speed) [CmBase]
*= LS Weight(+50%) Flight mode(T1-thermal) Offset(
...Continue Reading
Posted by Miami Mike | Nov 15, 2016 @ 09:19 AM | 16,749 Views
How to Turn Your Backlight On and Off Without Tying Up a Useful Switch

In Mike Shellim's F3J/TD setups, both Version 2 (F3J_200_X and F3J_200_V) and Version 3 (F3J_300_X and F3J_300_V), logical switches L1 through L5 are used to manage the Calibrate mode. Calibrate is enabled by holding the right stick in the lower-left corner (assuming Mode 2) while activating SH↓, and it's released by activating SH↓ alone.

Also, in Version 2 the backlight is switched on and off with SF↓ and SF↑ respectively, via Special Function 4. This appears to have been eliminated in Version 3 but could easily be added by the user if desired.

The following is a programming method I use that leaves Mike Shellim's Calibrate mode untouched while allowing SH↓ to also toggle the backlight on and off, freeing SF for a more useful function. When your radio enters Calibrate mode, which is normally used when your model is indoors where you might actually need the light, the backlight will automatically be on. In other flight modes the backlight will be off by default, but can be toggled on and off by flipping SH↓.

This programming can be combined with my SetFail flight mode for setting failsafe in flight, which is activated by holding SH↓ for one second, resulting in SH having three different functions:
  1. SH is used to enter and exit Calibrate mode as per Mike Shellim's setups.
  2. SH is used to toggle the backlight on and off.
  3. SH (held for one second) is used to
...Continue Reading
Posted by Miami Mike | Nov 13, 2016 @ 12:07 AM | 18,486 Views
Add Bluetooth to silently monitor your Taranis telemetry!

Bluetooth transmitter from Amazon

Bluetooth receiver from Amazon

If the receiver is unavailable, here's a search for similar items.

This one looks good.

Here's the Bluetooth transmitter mounted to the back of the module compartment cover with double-
sided sticky tape. There's a notch cut out at the bottom corner for the audio cable to pass through.
...Continue Reading
Posted by Miami Mike | Nov 12, 2016 @ 04:39 PM | 17,806 Views
When it comes to setting failsafe configurations that determine what our models will do if and when they lose radio contact, we usually just take a wild guess about what position each control surface should take. Then we face the very scary prospect of turning off our radios in flight to test those settings, hoping that we'll be able to regain control in time. I've never had the nerve to try that and I'll bet very few others have either.

Here's my method for setting failsafe:

First of all, on the Taranis MODEL SETUP page for each model, the options for Failsafe mode are Not set, Hold, Custom, No pulses, and Receiver. I had at first set mine to Receiver, which means when you press the F/S button on the receiver it memorizes the current control positions and uses them as its failsafe configuration. I've since switched to Custom and added a note to the end of this post about why that appears to be a better choice than Receiver.

For setting failsafe I used what was my next available flight mode, which was FM8, to which I assigned the name SetFail. I set all four trim settings to Own Trim and set the SetFail mode to be activated by a Logical Switch which I'll call L4 for this example. L4 becomes false and SetFail is deactivated the instant either the aileron or elevator stick position is moved from center. In Mode 2 that means the instant the right stick is moved.

I added these mix lines to determine what the trim switches do while in SetFail mode. I fly gliders,...Continue Reading
Posted by Miami Mike | Nov 12, 2016 @ 08:41 AM | 18,228 Views
Here are my current Taranis X9D control assignments for sailplanes:

My radios have 3-position switches in place of S1 and S2, as described in Taranis: Change S1 & S2 to Switches. The switch positions are labeled S1↑, S1-, S1↓, S2↑, S2-, and S2↓.

My model memory setups are based upon Mike Shellim's F3J/TD Version 2, with substantial modifications, some of which are adopted from his newer F3J/TD Version 3 setup. You can find his competition glider setups at

  • SE Different Functions for Pure Glider and Motor Glider Versions
    • Pure Glider Version - Flight Modes For Winch Launching. Flap stick must be in full-up position.
      • SE↑ Zoom mode. A separate elevator rate for Zoom mode is included on the Inputs page.
      • SE- Glide (Goes to the flight mode selected by switch SA.)
      • SE↓ Launch mode. Uses a separately adjustable combi mix that reads the aileron stick directly and is independent of aileron rates.
    • Motor Glider Version - Motor Control Motor must be armed.
      • SE↑ motor full power
      • SE- motor half power
      • SE↓ motor off. SE must be in this position before motor arming is possible.
  • SF Select Landing Mode When the flap stick is moved away from the top position either Flap mode or Crow mode is activated, depending upon the position of SF.
    • SF↑ Flap mode (flaps only) with separate elevator compensation curve and weight setting.
    • SF↓ Crow mode (flaps down, ailerons up)
...Continue Reading
Posted by Miami Mike | Nov 12, 2016 @ 08:31 AM | 17,325 Views
If 3-position switches (short or long) are wired in parallel with the S1 and S2 potentiometers ("pots"), the pots are left in their center positions (very important), insulated, and stored inside the radio, and the switches are installed in their places, the following six additional switch functions will be available:

S1↑ S1− S1↓ S2↑ S2− S2↓ (Of course these designations won't show up on your radio screen or in Companion but they can be useful in your programming notes.)

Decoding S1↑ and S1↓ with Logical Switches:
L1	a~x S1  100 ---- 0.0 0.0 L1 = S1↑ 
L2	a~x S1 -100 ---- 0.0 0.0 L2 = S1↓
These two Logical Switches may be reversed, depending
upon which way the 3-position switch is installed in your radio.
If S1− represents a default setting then it might not need to be specifically decoded, otherwise it can be decoded with a third Logical Switch:
L3	AND !L1 !L2 ---- 0.0 0.0 L3 = S1−
The code for S2 is similar:
L4	a~x S2  100 ---- 0.0 0.0 L4 = S2↑ 
L5	a~x S2 -100 ---- 0.0 0.0 L5 = S2↓
L6	AND !L4 !L5 ---- 0.0 0.0 L6 = S2−
To wire a 3-position switch in parallel with a pot, use short insulated jumper wires to connect the top terminal of the pot to the top terminal of the switch, the center terminal of the pot to the center terminal of the switch, and the bottom terminal of the pot to the bottom terminal of the switch. Remember that the pot has to stay connected even though it won't be accessible, and it has to be set to the center detent position.

If you want to reverse the modification later it won't be necessary to disconnect or remove the switch. Just set it to its center position, insulate it, store it away inside the radio, and put the pot back where it used to be. Remember that in either case the control that's not being used must remain set to its center position.