Telemetry - do you use it? What do you think of it?

[Richard Sharman]

Posted by Wingman on 06/09/2011 09:03:13:

..... for us model flyers the bees knees of telemetry would be a stall warning device.

 

I've been an enthusiastic user of the EagleTree telemetry system for a number of years now, and long ago implemented a stall warning alert based on the airspeed measurement. The onboard unit measures and logs airspeed (with a pitot tube sensor) every 0.1sec and transmits it to the ground unit (in your pocket, held by helper, whatever). When the airspeed falls below a given threshold (set by you) a warning bleep sounds (just like in a fullsize cockpit). The total delay from detection to warning is negligible.

 

The only question is how to set the threshold? I did this by deliberately stalling the aircraft a number of times at height, and then checking on the log to see what the typical airspeed was at that point. Then I set the threshold just a little higher giving a "stall onset warning". Oh, and I knew exactly when the stall occurred because I could check it against the log value of altitude.

 

It's most useful on the last stage of the landing run when it's easy to slow the plane too much, resulting in a sharp touchdown, or worse, incipient spin.

 

Now I have a DX8, but it's short on sensors ( I'm using battery voltage, and temperature sensing on the cylinder head but would like rpm etc). I'm just acquiring an airspeed detector and hope to re-implement the stall warning function on other models soon.

[John Privett]

Full size Cessna 150s (and probably many other light aircraft too) have a mechanical stall alert that works by air pressure at a specific point on the wing.

 

I've never worked out exactly how it does this, but it must be activated by low-pressure air immediately in front of the device which is on the leading edge of the wing. One of the pre-flight checks is to check it is working by sucking and listening for it to buzz. (A handkerchief placed over the hole is recommended when doing the check in case any insects have taken up residence in the device!)

 

It's the square hole in this pic.

 

 

Maybe something similar could be done in a model - though sending a signal via the telemetry rather than just squawking! It must be more accurate than a speed-based warning.

[Danny Fenton]

I guess the Cessna's I wasaround were a bit older than the one you show John. The ones I remember simplay had a metal vane that stuck forwardinto the airflow. This blade was simplay attached to a switch. When the airflow was getting close to the stall it would push the vane/blade up and trip the switch, sounding a buzzer in the cockpit.

Here it is on an old Cessna

I guess it makes sense the more modern has a pressure sensor, but the early method does make me think something simpler is possible for us modellers. We could certainly cause a very bright led to light on the stall, and as we generally land towards ourselves (sort of) then it stands a chance to be seen perhaps?

 

Cheers

Danny

 

[Vecchio Austriaco]

Now we have to find a victim who will put this into a model. Don't think it will match your Spit Danny. What is your next project

[Danny Fenton]

Yes that would be good, anybody up for a challenge? You could fit it in a wot4 to test the theory

Next project is probably to finish my Hurricane

Cheers

Danny

[Erfolg]

I am sure that we have some members of this site who are practical Instrumentation and Control Engineers. Their practical and theoretical knowledge of fluid flow theory and devices could be useful in the development of model appropriate solutions.

 

The pitot tube being a conventional pressure measuring devices, used in industry in both piped and duct systems, more familiar to us in aircraft. There are at least 5-10 types of pressure measuring types, but the pitot tube has an advantage in that it susceptibility to being inline with the fluid flow, works to an aircrafts advantage. Its disadvantage is the tube, which is liable to damage, and initial siting and alignment needs to be as typical for all conditions of the flight envelope.

 

However I have come across a large range of devices which may have some merits

 

a) Doppler systems

b) Vortex Shedding (Von Karman?).

c) Optical

d) Venturi Meters

 

All are used in the perto chemical industry. I have spent many unhappy hours being berated with respect what is needed to achieve a representative measurement.

 

To my mind the ingenuity of I&C engineers in getting their devices to work, could well be turned to modeling usage.

 

As a mechanical engineer i did not like, anything sticking into the pipework, as maintenance caused issues with fluid loss, interrupting operations. I guess in a similar vane, I would prefer a surface mounted device, which does not have anything flimsy sticking out, which could become damaged or its operation compromised. A solid state pressure switch/load cell type idea would appeal if it worked.

[Richard Sharman]

The key parameter to measure is "airspeed". When airspeed falls below the normal range a stall is possible. This can happen because of slow flight, tight turns, etc. The alert a pilot wants on an incipient stall is an audible warning of some kind. The EagleTree system allows many types of bleep, which I have used. The DX8 however has only one bleep, so when you hear a bleep you don't know what condition caused it. So, just land and investigate.

The fullsize Cessna 150 and 172 I used to fly had pitot tubes projecting into the airflow. Stalling is indicated by an unpleasant buzzing noise. One of the pilot checks on the standard checklist was "check pitot clear and operating". Since this is such a standard sensing device, tried and tested, I don't see the need to invent anything new.

 

The stall warning pitot device I implemented on my twin islander was a simple tube pointing into the airflow. The stall warning pitot device I implented on my Cessna Skylane was similar. It's hard to see in these photos though, I'll look for a better one.

 

Spectrum are selling a pitot tube here.

I now have one of these and plan to put it into something soon, but it will just have to sound the universal Spectrum bleep !

[Erfolg]

I thought that a stall was more than just related to speed. I thought that it was also related to the rate of change in the direction the aircraft was traveling, essentially the rate that the angle of attack changed relative to time and velocity.

 

I thought that was why the pitot tube worked well, as it sensed that a change was taking place, due to the disruption of the laminar airflow, into the tube.

 

I am only suggesting there may be other means of achieving a similar measurement, which had robust sensor. i do not know what, but hope that with time some one will come up with a good system that is better suited to model use. Because I am pretty careless with the storage and handling of my models.

[Richard Sharman]

Dear Erfolg --

see this for the theory of stalling (it's all about airspeed, not rate of change of AoA.)

 

also, see this for an explanation of how a pitot tube works (it measures the difference between static and dynamic air pressure, hence giving airspeed)

 

Meanwhile, On Message, back to Telemetry:

 

I now have the following working with my DX8:

Rx voltage (what the ESC delivers to the radio)

Motor voltage (Lipo battery pack voltage)

Temperature (can be motor, ESC, or I.C. engine cylinder head, or other)

RPM (of electric motor)

 

What I don't have working is:

RPM (of I.C. engine) because I haven't bothered yet

Airspeed -- because it needs DX8 Airware software v2 -- does anyone know about this? help would be appreciated.

[Erfolg]

Richard

 

Surely a high speed stall is all about the rate of change of the angle of attack, with respect to velocity (as a vector). It is discussed in the section under the section dynamic stall.

 

 

 

 

 

 

 

 

[Reno Racer]

Apart from when my countdown timer beeps at me telling me its time to start landing, I never look down at my TX when flying.

 

Telemetry sounds like a good idea, but like FPV, its not for me. (Maybe useful as a Head Up Display in FPV googles).

 

If i'm trying to look down and fiddle through telemetry options, then I'm not looking at the plane, just the telemetry software/module telling me my airspeed in increasing and altitude is decreasing......mm great this telemetry thing, I wonder what all that data means........CRASH!!!., ooops.

[Pete B]

Richard,

v2 update enabled the telemetry screens for additional functions. An extract of the Readme PDF is here:

 

Version 2.00

Software Upgrades
• DSMX is enabled.
• DSMX/DSM2 bind mode is now shown on the main screen immediately to the
right of the Spektrum logo.
• DSMX/DSM2 mode selectable on the Frame Rate screen. Note that a DSMX
receiver is necessary for DSMX operation.

• Added support for new Telemetry sensors Airspeed, Altitude, and PowerBox.

 

I'm running on v2.03 and haven't had any issues (I haven't any elevon models).

 

Pete

[Joao Miguel]

Posted by Steven Buckingham on 29/07/2011 01:16:43:

I'm a returning flyer and have just got myself a Hitec Optic 6 as a starter tx partly because HiTec seem to be a step ahead on the telemetry front? I think the opportunities of telemetry are great particularly the idea of a variometer on a glider!

 

To start with I'm looking to make use of the basic functionality included in the kit to set up the low battery warning for a 3 cell lipo. I got the HPP 22 setup eventually (v.poor instructions included, but a trip to http://hitecrcd.co.kr/tester/hpp_22.htm for the .exe got it functioning, and why couldn't they build it direct into the tx?)

 

Can anyone advise what the low battery warning should be set at for a 3 cell Lipo? I'm pretty conservative with my air time but a backup doesn't do any harm!

 

Thanks

I believe no one answered you so I will try. I am new with electrics as well but I have the Optic 6 and Aurora and learned how to use the HPP 22 to setup the low battery warning on the Spectra module (note that is on the module, not on the transmitter itself).

The key is when your ESC safety cut-off will kick in. You should have the warning from the spectra before that. Also, you have to make sure that when under load (and the voltage sags) the warning tells you that the end of the Lipo is close. if your ESC kicks in at say 2.8v per cell or 8.4v, I would adjust the HPP 22 to program the spectra module to warn you above that, say 9v.

If, like me, you moved to A123 LiFe batteries, the voltage will be at 2v but the ESC still is the one to look at as you will have to program it to cut off at the voltage you want. If you are running a 4cell pack it will be 8v for the battery but the ESC will not have that and you will end up using 8.4v... again, you can adjust the spectra to something above it, depending on how much the battery sags under load. Any other user with experience on that?

[Erfolg]

When I started to think of telemetry, I did think of what I wanted, I have found it hard to identify what. Identifying what is useful will probably develop with usage and the feed back to manufactures, with respect to what sells.

 

I think we are probably in a similar position to early Proportional Control. In that the equipment works, but is expensive. With time I would expect both the reliability to increase and costs to reduce.

 

I suspect that we are in the same position as the early Radios and ESC's. In that most of the gear is coming out of garage type manufacturing facilities. Many will attempt to move up to small wrinkly shed operations. With ESC,s, the difference seems to be that the quality ESC's are still hand made. On the other hand, the Chinese operations tend to use jobbing electronic companies, using pick and place and all the other mass production techniques, that are possible where capital equipment costs are recouped over many product contracts and lines. It can be argued that this manufacturing model, produces a low cost, with high in built quality item that the sheds/garage operations are hard pushed to replicate .

 

I was thinking about the alternative to Pitot tube, as I was maneuvering my indoor helicopter around the dinning room. I thought that back in the 70's when Morely made the first helicopters available, giros started to be fitted to them. In that era, each Giro cost a weeks wage, based on spinning rotor type technology. Now my £30 helicopters has a giro, I guess a solid state type device, I guess made for pennies, and it works well.

 

I then turned to Pitot tubes and the devices that others have highlighted. I also thought of Richards comments and realised I must have failed in explaining my aspirations.

 

I do know that pitot tubes are measuring the dynamic pressure, at the simplest level a "u" tube, with a nozzle poked into the fluid to be measuered. It does however have limitations, which can be an advantage. In duct work, obtaining an accurate Isokentic Measuerement, is an issue, in that there is a "velocity profile" from the surface to the free stream. Also the orientation and positioning can be an issue, as well inlet issues. Finally afer installation there is the issue of determining that what is recorded, is what is flowing, or calibration. The advantage of the tube on aircraft, is that it is recording the velocity (direction as well as the scale) not the speed (scaler). With respect to a model, if speed is only measured, it is possible that the body is moving at high speed, sideways for instance, but the wing has a low speed. The pitot tube measure along a single axis(which is good). It is the positioning and fragility of the pitot tube, it,s small bore on a model making keeping the bore to the transducer clean a possible issue.

 

I have seen somewhere a venturi type device for measuring airspeed. The principle being the same as a "Orifice plate" which use Bernoulli principle to equate pressure drop to velocity. Again there are practical issues with respect to models.

 

I am hoping as with giro,s some bright spark comes up with a surface mounted, solid state transducer for models. On a similar lines to the development of the giros from expensive, fragile devices, to the dirt cheap device which takes all the abuse in my dinning room. The trouble is, that once someone demonstrates how it could be done, everyone can and will do it, making a fortune from the concept will be a challenge. The garage operation is quickly left behind. After all Futaba RC fame is not based on breaking new ground, that was the pioneers that have been long forgotten such as Doug Spreng.

 

I know some seem fixated with beeps, yet you do not have to a an audible output that the whole world can hear. Yet if you are IC orientated, what are a few beeps?

[Richard Sharman]

Posted by Erfolg on 08/09/2011 20:10:50:

....Surely a high speed stall is all about the rate of change of the angle of attack...

yes,, but that's only relevant for heli's, bumblebees and propellors -- we're talking about fixed wing practice here !

[Richard Sharman]

Posted by Christian Ackroyd on 08/09/2011 20:19:31:

....I never look down at my TX when flying......

Nor do I !!!! When I'm instructing I always tell the student: "look at the model !" .

 

Telemetry systems usually come with an audible alert ( a bleep), some with a tactile alert (a buzz). I have used the services of a "crew member!" who stands by me and reads out data as and when asked. You can think of other methods.

 

The great value of telemetry is that it starts to tell you what is going on in your model while it's in flight, so I can't imagine anyone who wouldn't want to know that -- certainly I do ! Even if it only gives me an early warning of a problem so I can land and investigate it would be worth it. If it helps educate me in how well the model is flying and what it's doing that's a bonus, and I might make use when I trim the plane, design and build a new one, etc.

 

If you don't want to bother and are happy flying the way you do, then fine ! But for others it's interesting, and a challenge.

[Richard Sharman]

Posted by Pete B on 08/09/2011 20:35:12:

...v2 update enabled the telemetry screens for additional functions....

 

That's good news, Pete. Could you post a link to the Readme PDF fo v2, please ? I've looked everywhere I can think and can't find it -- must be looking in the wrong places? I obviously need to download v2 soon.

 

thanks, Richard

[Richard Sharman]

Posted by Erfolg on 09/09/2011 11:27:34:

.....I was thinking about the alternative to Pitot tube....I am hoping ...some bright spark comes up with a surface mounted, solid state transducer ...

 

Well, yes, that would be wonderful, but what physical principle would it use to detect, and therefore measure, properties which are relevant to the flight ? To be useful a sensor has to respond to some variation in the natural world, while being relatively independent of other variations. Not easy sometimes, but it's a well researched area of study so plenty of devices exist.

 

The solid state device which does assist in motion detection is of course the GPS navigation device. I have used the EagleTree GPS sensor for a number of years (it's the size of a small postage stamp, and not much heavier) and is very successful. It gives full Gps positioning data, plus speed, direction of travel, etc. But, of course, this is Ground Speed -- not Air Speed. So while it tells you where your model is (was), and how fast it's travelling over the ground, it doesn't tell you whether you're near the stall.

 

So for stall warning it's airspeed detection you want, and the pitot tube does a good job of this. Of course if your plane is sideslipping badly, in a spin, whatever, then the measurement could be misleading, but we are intelligent and take account of such things. The case to guard against (as in fullsize practice) is where you think you're flying normally, but have actually strayed close to the stall, sometimes too close for comfort --- then a warning could be useful ?!

 

I think the key question to ask about whether telemetry is good for you is "what information do I need to make my model fly better?". If nothing, then fine, carry on as you are. But I have found that knowing the sort of information I would get in the cockpit of a fullsize plane does help me, so I go for it. Also, the logging of historical data (the last few minutes of the flight, indeed) can help in diagnosis, especially of accidents. So the introduction of telemetry to mainstream model flying is a good thing, albeit in it's early stages as yet, and we should generally welcome it.

[Pete B]

Hi Richard,

 

You need to log in to the Spektrum Community site. Once you are in, click on the Updates button which will take you to a list of the updates.

 

Immediately below the download button for each version, there is a link to 'download the Software Update Read Me file'.

 

That will produce a PDF text file which outlines all the changes made by that version, together with all the changes made in the earlier versions.

 

If for any reason you can't get into the site, PM me and I'll send you a copy of the PDF.

 

Pete

[Sandy Colquhoun]

Hi folks, just wanted to add a note on my experience with telemetry, which has only been during this year, since I bought a Graupner system. I found their Smartbox to be not all that smart, or maybe it`s me, however the system does work well provided you programme everything on the tranny, except the vario which can only be set up on the smartbox.

I only use the signal strength meter(built in) and a variometer.

I agree with everybody who has doubt about reading a screen while flying a model, don`t do it, get another club member to read off the figures if you really need them, never take your eyes off the model.

On this set there`s an alarm for low signal strength, and several little tunes for vario settings. You don`t have to know everything all the time, so you don`t need to set the whole orchestra. In my case, all I need is- am I in rising or falling air, just two audible alarms with different sounds. The sound is very low, so I bought a hearing surveillance device for £6 on Amazon, tape the microphone to the tranny and put the earpiece in, problem solved.

Of course, 3 months after I bought my gear, Graupner revised the MX16 which now provides this function, and doesn`t appear to use the Smartbox., A commendable improvement.

The bottom line is that having the vario is a definite advantage, you know what`s happpening around the model, and no doubt other bits of kit will be equally useful for different kinds of flying, but I`d be cautious about adding other functions unless there was a real and foreseeable benefit .

 

 

Here`s to better weather

Sandy

[Pete B]

 

For whom it may concern, here is the text of the Airware Readme file. I've had to cut it in two as the forum doesn't seem to be able to cope with the whole text in one go:

DX8 Spektrum™ AirWare™

Change Log
Version 2.03
Software Features
• Changed Monitor screen to improve perceptibility of changes in stick and trim
resolution.
• Added new wing type Elevon B. This mode is used if control horn or servo
positions don’t allow correct throw directions. Eliminates need to swap elevator
and aileron servo leads. Also required with some trainer systems like the DX6i.
• When editing the timer configuration, any changes will cause the timer to be
reset.
• After reversing the throttle channel, the screen changes to show a reminder to
rebind at low throttle for safety.
• To improve the ease of adjusting travel limits for complex servo functions (swash,
V-tail, etc), the Servo Setup screens now are tracking servo outputs directly.
• To avoid confusion when binding, we changed the Bind screen to show actual
11ms/22ms bind info instead of what the receiver is capable of doing.
• Enabled adjustment of the telemetry receiver voltage display bar. Adjusting the
low and high setpoints (high is NOT an alarm) you are adjusting the scaling of
the bar graph for Rx Voltage.
• When importing a model, a confirmation screen now appears to warn about
possibility over-writing the wrong model.
• Changed telemetry menu and capabilities to enable access to future sensors.
• Users are now able to calibrate the knob and both stick in both axes. This is
done by selecting NEXT several times from the System Setup menu. Move the
sticks in a “+” format, NOT in an X or O. It is important not to push the sticks to
the corners.
Software Corrections
• Flap/Elevator Smoothness – Elevator compensation travel was not smooth
when there was significant trim on the elevator channel.
• Flap Overdrive – Initial flap movement could sometimes cause flaps to jump to
one extreme of travel before moving to correct setting.
• Telemetry - Changed scaling for telemetry alarms Altitude & Airspeed. Fixed
‘hidden status’ screens when using models created in older versions.
• Translations – Improve/Correct translation of some terms for German, Spanish
and Italian modes, particularly on the Timer and Telemetry screens.
DX8 Spektrum™ AirWare™
Change Log
Version 2.02
Software Upgrades
• Changed Monitor screen to improve perceptibility of changes in stick and trim
resolution.
NOTE: Version 2.02 is a Factory only version.
DX8 Spektrum™ AirWare™
Change Log
Version 2.01
Software Corrections
• Language translations corrected in telemetry and helicopter screens.
• Timer screen allows access to change throttle stick position.
• Telemetry screens for PowerBox and other sensors are not shown when the
Display control is set to Inhibit.
• A model file that has the timer set to Inhibit can now be imported correctly.
• Flap system output positions are updated immediately as changes are made.
DX8 Spektrum™ AirWare™
Change Log
Version 2.00
Software Upgrades
• DSMX is enabled.
• DSMX/DSM2 bind mode is now shown on the main screen immediately to the
right of the Spektrum logo.
• DSMX/DSM2 mode selectable on the Frame Rate screen. Note that a DSMX
receiver is necessary for DSMX operation.
• Added support for new Telemetry sensors Airspeed, Altitude, and PowerBox.
• Receiver Voltage is now shown on the Min/Max screen.
• Telemetry menu is now a scrolling list, to improve ease of use as the number of
possible sensors increases.
• When setting the Flight Pack Voltage alarms, you can easily set the alarm points
based upon LiPo cell count, then tweak them to your preference.
• The low-level SD interface is updated to improve compatibility with PC’s.
• Mix and Gear switches can now be used in mixing functions to have the active
position either 0 or 1. These are named Mix-0/Mix-1 and Gear-0/Gear-1. The “1”
option is the same as the old Mix or Gear option, as the mix function was
previously active in position 1.
• The Timer Setup screen now hides information which is not related to the
selected timer mode.
• In Elevon wing types, the Flap System is enabled, providing the flap function on
Aux 1 and enabling proper elevator compensation. In this mode, the Aux1
channel would typically be used either as a drag brake or a spoiler.
• The Serial Number screen now includes an EXPORT function to make it simpler
to enter the serial number when registering a new radio.
Software Corrections
• Mix Switch – The Mix Switch was sometimes treated as a 3-position switch.
• Mode-Change Recalibration – When changing between Mode 1 and Mode 2,
the throttle and elevator sticks were calibrated to different tolerances than during
factory calibration.
• Telemetry Alarming – Corrected problem with multiple alarms on main voltage
sensor inter-acting with one another.

[Pete B]

...and here is the rest:

 

DX8 Spektrum™ AirWare™
Change Log
Version 1.05 (Not Released)
• All 1.05 changes are released in 2.00.
Version 1.04
Software Upgrades
• Trim Center Pause – When adjusting the trims through center, the pause was
lengthened to allow the center position to be more easily accessed.
• Knob Center Tone – When adjusting the knob, it generates a “center trim” tone as it
rotates through center.
• LiPo Battery Verification – Attempting to change the battery type in the Extra Settings
screen from NiMH to LiPo will not be allowed until a LiPo battery is installed. This
prevents the user from mistakenly selecting the LiPo battery voltage cutoff with a NiMh
battery installed.
• Frame Rate Defaults to 22ms- The Frame Rate now defaults to 22ms rather than
11ms. This prevents analog servo compatibility issues in the default mode.
• AirWare Auto-Update – To guard against inadvertently downgrading the radio’s
AirWare, after installing version 1.04 or higher the system will rename the update file to
prevent it from auto-loading in the future.
• Startup Screen – The startup is changed so that no inaccurate “No RF Link” warning is
displayed.
Software Corrections
• Heli Mode Trainer Button – if the Trainer button was assigned to a channel in the
Switch Select screen, the channel was inactive.
• Flap Trim – When a Flaperon wing type was selected and the right or left trimmer was
assigned to flap trim, the trim was mixed as ailerons instead of flaps. It was also not
possible to deactivate flap trim once selected.
• Acro Throttle Curve – Pressing the CLEAR button could allow the displayed throttle
curve to not match the values entered numerically.
• German Timer – The prompts for the German-mode throttle-based timer controls were
renamed so as to be more intuitive.
Throttle = Gasstellung
Throttle 1-time = Motorstart
Throttle Out = Motorlaufzeit
Version 1.03
Software Upgrades
• Heli Servo Travel Adjust – In heli mode, it is now easier to set up the swash endpoints
using the Servo Travel screen. The travel limit box remains on the last value that was
highlight by the stick position. Centering the stick and pressing clear returns to
highlighting both values.
• Enhanced Telemetry Status Screen – A new “All-in-One” telemetry screen displays
Timer, RPM, Battery Volts, Temperature, Rx Volts, Frame Losses, and Holds.
• Telemetry Auto-Display – An Auto option in the Telemetry Settings screen will
automatically advance from the main screen to the above Enhanced Telemetry screen
when the timer is activated and telemetry data is available. The roller can then be used
to access any of the telemetry or main screens.
• SD File Navigation – On the SD file navigation screen the BACK button now operates
the same as selecting the <BACK> file.
Software Corrections
• Heli Mode Mix Issue – In the previous version, mixing to certain channels would cause
no travel.
• Differential issue- In airplane mode when any dual aileron wing type was selected and
a mix was created with the left aileron as a slave (crow mixing) adding differential could
cause servo output errors on the aileron channels.
• Model Save Corruption – If there was an error while exporting a model, it could go
undetected and unreported until reading the file back in.
• Heli Bind Issue – If a model had Expo enabled on all throttle and pitch curves, it would
not bind. This is corrected.
Version 1.02
Software Corrections
• Heli Mode Model Memory Issue – In previous software versions, changing the channel
in the Gyro or Governor screens from the default setting to any other channel would
cause the model memory to default to Model #1.
• Heli Mode Limited Trim – Throttle Trim didn’t work below ½ trim.
• Direct Model Access 10-Second Timer – In some instances, the 10-second time-out
function for direct model access was applied to other screens after Direct Model Access
was used.
• Improved Flap Switch Selection – In Airplane mode, flap switch selection could be in
conflict in the Flap System Screen and in the Switch Select Screen. In version 1.02, the
flap switch selection is in the Flap System Screen.
• Center Trim Position Mark – Version 1.02 locates a trim tick-mark next to the trim
graph at center trim, allowing convenient reference when the cursor is near center.
Version 1.01
Software Upgrades
• “Throttle Out” timer activation – In the timer screen, Throttle Out has been added to
the timer start options. When selected this mode uses the throttle servo output position
to activate the timer rather than the throttle stick position. This is ideal for electric
helicopter use as the timer can be paused when the output throttle position is at idle
even though the stick may not be at low stick (like during an autorotation) plus the timer
won’t turn off when doing full negative pitch maneuvers in stunt mode. MIX and GEAR
switches have also been added to the list of available timer switches.
• Throttle Reverse Confirmation – In the servo setup screen, when reversing the throttle
servo, a confirmation screen is now displayed requiring a second step (confirmation)
before servo outp

[Richard Sharman]

Posted by Pete B on 10/09/2011 21:07:48:

...You need to log in to the Spektrum Community site......

 

Thank you Pete for the helpful advice, and posting the Spektrum update info. My DX8 had been back for the general recall, and I had assumed it was therefore at the latest level -- but no! it was at version 1.04.

 

Registering me with the Spektrum Community site was easy, but registering the DX8 took a bit as I persistently and willfully misread the serial number. Eventually I got my zeros and O-s sorted out and registered, downloaded the software, installed and tested. All ok! As there were reported problems with ver 2.03 which Spektrum are fixing soon, I elected to go to ver 2.01 for now, and upgrade again later.

 

So now I have airspeed, temperature, rpm, main voltage, rx voltage, radio outages, but no altitude as I don't have the sensor for that -- joy at last !

 

Richard

PS hope you like the new thumbnail - my West Wings Hawk (and me)

[Richard Sharman]

QUESTION:

 

is anyone using "logging" with Spektrum telemetry ? (i.e. the ability to record all the measurements during a flight, so that they can be played back later)

 

On the EagleTree system data can be logged onboard and later played back after the model is recovered. It the EagleTree unit is transmitting data to ground (telemetry) it can be recorded or displayed in real time.

 

Is there a Spektrum equivalent of this function, and if so, how does it work ?

Help appreciated, Richard

[Pete B]

Timbo uses an EagleTree logger as a stand-alone system, Richard.

 

Apparently Spektrum will have a recording function on the DX10T Tx, the release of which which I believe has been put back again to the end of the year.

 

It is not currently available on the DX8, presumably to maintain the function advantages of the 10T. Whether Spektrum will make it available in future software updates of the DX8 is something they are keeping close to their chest........

 

I suppose it depends on whether it is possible, with the existing hardware of the DX8, to enable data-logging on the SD card, by software alone.

 

Pete