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Posted by Miami Mike | Dec 15, 2023 @ 11:18 AM | 4,936 Views
Academy of Model Aeronautics members can now get a custom AMA number.

The charge is $50 and the restrictions are:
  • Each and every membership call sign or number must be unique. No duplicates will be allowed.

  • Only Life Members may use an all numeric preceded by an L.

  • Character sets that are obscene or inappropriate will not be allowed.

  • Alphanumeric combinations are limited to a maximum of 10 characters. This includes

    • all uppercase letters of the alphabet

    • numbers 0 through 9

    • symbols # – + & /

  • No spaces are allowed.
To update your membership, visit: www.modelaircraft.org/callsign.

And if you do, please check in here with your new AMA number!
Posted by Miami Mike | Sep 22, 2023 @ 11:57 AM | 8,456 Views
I remembered that I had this old safe in storage. It's very heavy and not easy to dispose of, so I decided to put it to use.



I disabled the locking mechanism, covered it with foil insulation to help keep the sun off, and put it out on my screened-in back patio.



It has four holes in the bottom where I used to have it bolted down, so now it has some ventilation in case pressure builds up inside.

...Continue Reading
Posted by Miami Mike | Sep 13, 2023 @ 12:24 PM | 7,605 Views
From a just-received AMA email:
Quote:
As AMA anticipated, the FAA has announced they are extending the Remote ID enforcement date by six months. Operators now have until March 16, 2024 before they will have to comply with the rule. This extension provides the FAA more time to approve FRIA applications and manufacturers the time for production of broadcast modules. For the FAA’s full statement on the extension, click here.
It was September 16, 2023, now it's March 16, 2024.
Posted by Miami Mike | Jul 09, 2023 @ 11:46 AM | 47,982 Views
Open for later use.
Posted by Miami Mike | Oct 14, 2022 @ 03:03 PM | 12,534 Views

Coming soon:

2024 Florida Soaring Contests
and other r/c soaring events of interest

Posted by Miami Mike | Jun 13, 2022 @ 12:30 PM | 28,678 Views
Everyone with FrSky gear should check out the new Uni-RX A new firmware for FrSky ACCST receivers thread in the Radios forum, started by Wayne of Aloft Hobbies.
Posted by Miami Mike | Apr 17, 2022 @ 08:41 PM | 41,977 Views
A voltage-based version of the LiPo fuel gauge for OpenTX showing the percentage of fully-charged LiPo battery voltage remaining before your pack voltage will have decreased to your chosen cell voltage minimum.

Introduction

My first version of the LiPo Fuel Gauge is based upon milliamp-hours (mAH) measured by a current sensor and calculated by an OpenTX "Calculated" sensor. It displays as a percentage the estimated mAH remaining in a LiPo battery by subtracting the mAH consumed from the mAH that's available from a fully-charged pack. However, many are rightfully more concerned about not draining cells below the recommended voltage level, which could damage or shorten the life of a LiPo pack. The LiPo Fuel Gauge V2 will show as a percentage the amount of voltage remaining before you reach your chosen total pack minimum. A reading of 100 means the pack is fully charged, and 0 means the pack is discharged to its minimum.

This can be set up to watch a pack's output voltage whether you're using a "VFAS", "A2", or any other type of voltage sensor that reads your pack's total output voltage. You can even set up alarms and/or voice announcements to alert you, or to report the voltage value whenever you activate a switch. It can be set up to detect and adjust itself to the number of cells in the pack. And if you have an FLVSS or MLVSS sensor you can set it up to work with the total output voltage along with its usual function of displaying...Continue Reading
Posted by Miami Mike | Oct 26, 2021 @ 09:26 PM | 47,755 Views
Introduction



A full-scale sailplane pilot told me that the yaw string is the most important instrument in a sailplane. It's hard to believe that it's more important than the airspeed indicator, altimeter, or vario, but he was very clear that the yaw string is important, even though it's just a piece of yarn taped to the canopy. Apparently without a yaw string it's hard for a pilot to tell if his glider is making a coordinated turn, meaning that the fuselage is aligned for minimum drag as the plane turns or circles. So if it's difficult for a pilot sitting in the cockpit then it seems reasonable that it would be difficult for an R/C glider pilot on ground. The yaw sensor is meant to serve as the equivalent of a yaw string for radio-controlled sailplanes.

This is a project that I started a couple of years ago but didn't do much with it until recently. It works with OpenTX / EdgeTX radios and telemetry receivers. A voltage sensor is required, such as the AIN2 input that many FrSky receivers have. When working in conjunction with a Lua script it will produce beeps to indicate how far from center the fuselage is aligned and in which direction. An adjustable "window of silence" stops the beeps when the sensor is aligned with the fuselage.




Next: Building a Yaw Sensor

...Continue Reading
Posted by Miami Mike | Oct 01, 2021 @ 11:16 AM | 52,101 Views
Double centering is a problem where the center position of a control surface differs, depending upon which side of center the control surface was at before it returned. Using the rudder as an example, you move the rudder stick left and then back to center, and observe that the rudder has stopped slightly left of center. Then you move the rudder stick right and then back to center, and observe that the rudder has stopped slightly right of center.

Of course the first step in trying to correct this problem is to work on the model, tightening the linkage, changing its geometry, eliminating binding, replacing a worn or cheaply made servo, fixing a damaged hinge, etc. In general, you try to eliminate slop where you can.

But if all that fails and you still have some double centering that you'd like to reduce further, or perhaps even eliminate, and your radio runs on OpenTX, you may be able to reduce or eliminate the problem with radio programming. The idea is to program the servo to move the control surface from its extended position toward, and then slightly past center, just enough to compensate for the play so that it stops at the same position when coming from either direction.

Here's an example using the rudder:
  1. Choose a global variable to set the amount of extra travel past center. In this example I'll use GV1. It should be set to a minimum of zero, and for the maximum a value of 10 seems reasonable, although more may be needed in extreme cases. Make sure the GV is
...Continue Reading
Posted by Miami Mike | Aug 18, 2021 @ 11:23 AM | 59,319 Views
SD Card Version Editor
For OpenTX "Taranis"-style radios without color screens
(An updated version that also works with color screens may be coming, depending upon interest.)

Many OpenTX users have customized and contributed to the data on their SD cards with their own voice announcements, scripts, images, log files, and other additions and changes that they don't want to lose by updating their SD card contents when they upgrade to a newer version of OpenTX, especially when in most cases it's not really necessary. However, if you don't upgrade the SD card contents then when OpenTX powers up and reads the file named "opentx.sdcard.version" in the root directory of your SD card, it gives you an "SD CARD WARNING" message saying what the expected version is, and then your radio won't continue powering up until you press a key.


A popular workaround is to edit the opentx.sdcard.version file to say what OpenTX wants so that the warning message will go away, and here's a tool named "Edit SD Version" that makes it easy to do that with your radio. When you get the warning message after an OpenTX update, all you have to do is note what the expected version is, select the tool, edit the file with your up and down buttons or rotary knob, along with your enter button, and then select "Save and exit". If you then turn your radio off and back on you should see that the warning is gone.

Download Edit SD Version.lua and store it on your SD...Continue Reading
Posted by Miami Mike | Jul 22, 2021 @ 04:29 PM | 53,400 Views
Stair curves are used to divide analog input values into discrete steps. For example, the curve below, named "9st" (for "9 step"), will divide an analog source's output value into steps of -100%, -75%, -50%, -25%, 0%, +25%, +50%, +75%, and +100%.



Stair curves are useful during model setup to collect data for use in calibration of curves that are active during control of the model. Uses include calibrating and matching control surface positions, and calibrating elevator-flap compensation curves, which adjust elevator position for level flight at all flap positions. A compensation curve could also correct changes in pitch caused by changes in motor thrust.

The Ultimate Stair Curve

Curve "9st" above is a 16-point curve with 9 steps that can be used to obtain the data for calibrating a 9-point curve, but OpenTX supports curves with up to 17 points, and more points can mean greater precision when a curve is accurately calibrated. Single stair curves of up to 9 steps are possible, but I'll show here how to set up stair curves with any number of steps from 5 to 17, enabling precise pinpointing of the default X values for Custom X curves of up to 17 points. For stair curves of 10 to 17 steps, this is accomplished by combining two curves.

Here are the two curves used to create a 17-step stair curve. The first one is named "17P". The "P" indicates that it's applied to the positive half of stick travel:



And this one is named...Continue Reading
Posted by Miami Mike | Jul 05, 2021 @ 03:42 PM | 44,800 Views
The Problem With Setting Up Failsafe

The problem with setting up failsafe is that it's hard to know whether the settings you choose will put your model into the best configuration for cases where you lose radio control. A good solution should include these features:
  • You should be able to fly your model and make adjustments in flight so that you can monitor how your model reacts to your adjustments. For failsafe you would probably want to circle in a stable glide and gently descend.
  • While making these in-flight adjustments you should be able to quickly recover full control when necessary.
  • When you're finished, the settings should be preserved in your radio's memory so that after you land you can make them your new failsafe settings.
A Safe and Easy Solution

This is a revised version of the SetFail Flight Mode that I first introduced in 2016. It can be added to virtually any OpenTX model setup so long as it has an unused flight mode available, and it'll make it safe and easy to set up and test failsafe. Here's how it works:
  1. Fly your model to a safe high altitude and make sure it's trimmed for a level, unpowered, hands-off glide.
  2. Let go of the sticks and use one of your radio's momentary switches to select SetFail mode. In SetFail mode the trims are used to adjust control surface positions, and those trim settings will only be in effect while you're in SetFail mode. They won't affect regular flight.
  3. Use the elevator trim to adjust the elevator, the aileron trim to adjust
...Continue Reading
Posted by Miami Mike | Jun 14, 2021 @ 11:53 AM | 63,194 Views
The LiPo Fuel Gauge can't be set up in OpenTX version 2.3.10 or 2.3.11 due to an OpenTX bug that omitted the option of using telemetry sensors as input sources, but I'm happy to announce that's now fixed in OpenTX version 2.3.12.


Posted by Miami Mike | Apr 29, 2021 @ 05:36 PM | 43,507 Views
The OpenTX Mixes and Outputs pages should have been done like this:

Mixes



Outputs



If it were done this way then:
  1. Complex "aggregator" mixes that are read by other mixes could be grouped together with their final output mixes anywhere on the Mixes page instead of needing to be separated and located on high channels. It would be easier to construct and follow the program flow.
     
  2. Outputs would not have to come from the Mixes page when no mix functions were involved. They could also come directly from inputs, hardware switches, or logical switches.
     
  3. Mixes would have labels like "MIX1", "MIX2", instead of channel numbers, avoiding confusion with the actual channel numbers assigned on the Outputs page.
     
  4. Alternate mixing schemes could be added to the Mixes page and tested simply by changing the sources on the Outputs page, while keeping the original mixes intact.
     
  5. Rearranging channel assignments would be easy.
...Continue Reading
Posted by Miami Mike | Feb 16, 2021 @ 04:36 PM | 55,270 Views
If you haven't flown for a while and are having trouble remembering what each switch does on your Taranis X9D, X9D+, or X9D+ 2019, here's a telemetry script (that doesn't actually display any telemetry) that will show what each switch does in its current position, once you've edited the script to match your model setup.


The first lines of the script are meant to be configured by the user:
Code:
local max, min = 8.0, 6.0 -- max = fully charged radio voltage, min = lowest safe radio voltage.
local byrow = true -- Remove this to order switches down and across instead of across and down.

local slot = { -- There's room on the screen for a maximum of 16 characters for each switch position label.
	{type = "sw", id = "sa", up = "FM1: Crash", mid = "FM0: Cruise", down = "FM2: Burn"},
	{type = "sw", id = "sb", up = "aileron high", mid = "aileron medium", down = "aileron low"},
	{type = "sw", id = "sc", up = "elevator high", mid = "elevator medium", down = "elevator low"},
	{type = "sw", id = "sd", up = "rudder high", mid = "rudder medium", down = "rudder low"},
	{type = "sw", id = "se", up = "up is unassigned", mid = "md is unassigned", down = "dn is unassigned"},
	{type = "sw", id = "sf", up = &
...Continue Reading
Posted by Miami Mike | Feb 06, 2021 @ 11:52 AM | 51,621 Views
When setting up the LiPo Fuel Gauge with OpenTX Companion 2.3.11, 2.3.12 nightlies, and possibly 2.3.10, a problem has come up where telemetry sensors won't show up as selectable input sources.

When you use Companion to set up a new input for a model that has telemetry sensors listed on its Telemetry page, the sensors normally appear among the list of possible sources, like this:



... and when you choose one of those sensors as the source, the Scale field normally appears, like this:



However, in recent versions of Companion, telemetry sensors don't show up in the list.

The issue was reported on GitHub and a fix is in the works, and will probably be included in the release of OpenTX Companion version 2.3.12.

Also on GitHub, see this post and this post for updates.

...Continue Reading
Posted by Miami Mike | Apr 16, 2020 @ 01:52 PM | 57,735 Views
"You'll be glad when this it what? You didn't finish your sentence! Over."

Brian and Stewie Over (0 min 59 sec)

Posted by Miami Mike | Mar 19, 2020 @ 11:08 AM | 56,861 Views
The COVID-19 pandemic is real. Learn as much as you can about it from reliable sources and accept that you'll have to deal with it, because it's going to be with us for a long time and will get much worse before it starts getting better.
Posted by Miami Mike | Nov 30, 2019 @ 01:02 PM | 55,755 Views
Early in 2019 I won a Taranis Q X7 in a raffle at a club fun-fly. At first I thought I'd have no use for it because it doesn't have enough switches for my sailplane setups, but then I realized that an OpenTX radio can be useful for other applications beside controlling a model.

Presenting the OpenTX ALES Flight Group Launching System




...Continue Reading
Posted by Miami Mike | Oct 09, 2019 @ 08:06 PM | 56,664 Views
My Taranis X9D Control Assignments for Sailplanes
 
  • LS is replaced with a push-button that activates the Kapow function.
    • When the button is pushed the ailerons go up to their extreme limits, followed by the flaps after a 0.1 second delay to prevent flap-aileron collisions due to the wing's polyhedral break.
    • When the button is released the flaps return to their neutral positions regardless of the flap stick position, in order to prevent them from digging into the ground.
    • If the flap stick was down when the button was pushed, normal flap stick function is restored when the stick is returned to its up position.
    • Down elevator can also be part of the Kapow function and can be varied between the extremes of no down elevator (plane simply drops) to full down elevator (plane dives into the ground). TrmT (the throttle trim switch) is used to adjust the elevator position for Kapow while the Kapow button is held in.

  • SE has different functions for winch-launched gliders and electric-powered gliders.
    • When winch-launching a pure gilder,
      • SE↓ selects FM4-Launch mode. When in Launch mode, TrmT adjusts the amount of camber in that flight mode only, and TrmE (the elevator trim switch) adjusts the elevator position in that flight mode only. The flight mode is announced when it is selected.
      • SE↑ selects FM5-Zoom mode. When in Zoom mode, TrmT adjusts the amount of reflex in that flight mode only, and TrmE adjusts the elevator position in that flight mode only. The flight
...Continue Reading