FrSky Freelink

[Chris Bott - Moderator]

There appears to be a new app available for your smartphone or tablet.

Here's a quick preview of screens from my phone.

[Ron Gray]

Looks interesting. Chris, how do you connect it and which Rxs are supported?

[Chris Bott - Moderator]

I haven't seen it available in the android play store so had to download, unzip and install manually from here

[Chris Bott - Moderator]

Ron it appears to be early days. It looks like all X receivers.

Probably most useful for setting up things like stabilisers. I'm not sure how I'd use a live telemetry unit on a separate screen. Unless a spitter carried it so he can see readings?

It can be connected via transmitters that have Bluetooth i.e. those that support wireless buddy .

Or, it can be connected via an S.Port airlink S.

[Tim Ballinger]

I found that a couple of weeks ago but did not realise it was new!

i used it when testing out the motor setup on my recently finished cap 21. I had rpm, voltage, current from FrSky sensors all connected via Bluetooth from my Horus to the free link app on my iPad. I had the gps sensor on as well just for the hell of it.

Makes for my ideal motor test rig set with the data also being available in the telemetry log for post test/flight analysis. Non of it strictly necessary of course but I love working with the techy stuff.

Pity the app does not have a map display for the gps read out and a facility to read the tele log directly. Companion does the latter of course but although logging the gps output, is not able to display on the Horus 10. (The Horus 12 seems to be more capable ).

haven’t got a flight controller so not been able to test that part of the app which does the setup for you.

Provides a bit of fun while waiting for the better weather .

Tim

[Chris Bott - Moderator]

Sounds good Tim.

I'm still not sure of the advantage of displaying things on a separate screen when they can all be seen on the Horus one anyway, but I'm ready to be convinced.

Did you manage to arrange the parameters you wanted into the dashboard screen? If so, how?

[Tim Ballinger]

Chris,

They simply auto configured as soon as you touch the start button, because ,I assume , the senors are all S port. Actually had the temp sensors on as well ( they come bundled with the rpm sensor). Not tried the vario yet as that is part of a Rx which is buried in my glider somewhere but I will now that I think of it.

In the motor test scenario I described the advantage is all the parameters are on one page and (at least on a tablet) at a size which can be viewed from a distance ie out of the way of model and Tx.

In real flight, apart from a spotter, I guess it would be very useful for large complex models where the pilot has a luxury of a ‘flight engineer’ to monitor the models vitals. (Something I have always assumed the LMA guys use but I don’t know). Apart from that ,perhaps some fun for friends & family ?

Tim

[Ron Gray]

Interesting to see the Vario telemetry entry, I wonder if it shows what the one on my G8 RX does, altitude that jumps up and down so much it makes the read outs useless and ditto vertical speed read outs! (which is why I’m interested in the OpenXSensor).

[Chris Bott - Moderator]

OK thanks Tim

I was trying to get Power and mAh to show on dashboard but have failed so far.

[Tim Ballinger]

Chris,

i guess that’s because the dashboard is sensor orientated rather than derived quantities. Perhaps some coordinated feedback to the developers might give us a configurable menu system.

Ron,

i had a similar issue withe the vario bit linked the output to a logic switch only activated at above 2ft/s. When I say output I mean the ‘play vario’ beep viz just displaying or playing the vertical speed ( the latter really overworked the OS and the latency was measured in 10s of seconds. The beeps seem to work quite well once the noise is gated out. A long way from perfect but useable. I only glance at the integrated velocity (ie altitude) occasionally during flight and that is fine for me as the mark one eyeball filters out the noise at the low sample rate !

i will try it on the dashboard though and see if they have built in any sampling/ integration or damping before they display on that quite large linear display.

Tim

[Tim Ballinger]

Interesting. I just tried the vario output from my GRX8 on the dashboard. I had noticed the scale read in m viz m/s but had not really thought about it too much . So no surprise that despite being labels a variometer it actually displays altitude ( above sea level it seems) in my case 211m.

if you change to the sensor monitor it displays both vertical speed and altitude albeit the former exhibits the same high noise level discussed earlier. I suppose as as an analogue altitude display it serves a purpose but not much use for soaring.

Tim

[Chris Bott - Moderator]

Yes, in my opinion it will be much more useful if they ever make the dashboard customisable like the Horus telemetry screens are.

This afternoon I've failed to communicate with an S6R using this via the Horus. Maybe that just works via an airlink S ?

[Tim Ballinger]

Chris,

I see in the S6R/S8R manual that it says the free link only works With IOS version. Is that what you were trying with ?

Tim

[Ron Gray]

Thanks for the feedback re the vario Tim. I have the standard vario in another glider and that gives much more stable height read outs plus the vertical rise / fall gives out much better beeps. The GRX8 just cannot be relied upon to give accurate height read outs as they vary so much between readings and not just by a few feet, it can be hundreds! Absolutely no good for thermalling.

[Chris Bott - Moderator]

Tim no I'm using Android so that answers that.

I see it is available in apple App Store.

It isn't, in Android Play store so maybe it is new for Android, and not ready yet?

As you can see from my screenshots all the S6R/S8R stuff is there.

[Tim Ballinger]

Ron,

interesting about the vario, the GRX8//6 are both meant to have the high precision +/- .1 m variant viz the 1m of the Var N. Ie the same as the Var H. Are you using another standalone vario entirely? High precision might well equal high noise but a bit of a design flaw if that is the case.

i might fly the gps unit along with the GRX8 tomorrow and compare the tele log outputs afterwards just to check.

Tim

[Ron Gray]

It's the FrSky normal precision stand a lone vario Tim. Once reset at launch base it remains steady throughout a flight and doesn't fluctuate like the GRX8 does.

[Tim Ballinger]

So here are the plots for todays flight...

The first plot shows the whole 10 minute flight. The height as measured by the gps and the vario in the GRx8R are in pretty good agreement but as I would expect the gps altitude lags the pressure altitude by a small amount. The vereticle speed derived from the vario is incredibly noisy which is a problem because this is what drives the vario beeps.

The second graph shows a blown up segment with the thin blue line showing the vertical speed averaged over 20 data points. Still noisey but would be more useful when soaring.

The last graph shows the moving average line across the whole flight.

This is comparison is with the high precision variometer ( 0.1m) so I suppose it would be informative to also compare the low precision sensor which is only available as a standalone sensor.

Bottom line for me is the altitude as measured by the Rx8R vario is pretty spot on but the algorithm for the vert velocity is way too crude.

Tim

[Mark J]

I've had this app on my phone phone since I saw it on here. The other day I tried to pair a new bluetooth device and got an error of wrong password. After going through the usual reset,power up down clearing bluetooth cache etc. I was at the point of doing a factory reset of the phone. When I thought I'll try it in safe mode, success, pairing was OK. In safe mode most installed apps are shut down. Out of safe mode same problem. I then started uninstalling recent apps one by one, on uninstalling Free Link the Bluetooth started pairing again. I've found nothing on Internet about this so maybe it's just me? The phone is a Xiaomi Mi A1 running Android one version 9.

[Tim Ballinger]

Hi Mark.

I believe Bluetooth pairing problems are not uncommon especially after OS upgrades. I had problems with my iOS devices and followed the help which was reset network settings to default. Hey presto everything worked again. I think on Android the equivalent is refresh Bluetooth cache files. But google Bluetooth connection issues and you will find more definitive advice. As for the free FrSky app, not had any problems.

tim

[Chris Bott - Moderator]

Mark J that's a very timely post. Many thanks.

I had an Android OS update about a week ago and started having Bluetooth issues. I went through all the on line help I could find, including clearing Bluetooth cache and other networking resets. All I managed to achieve was the loss of connection to my car and watch. Whatever I tried wouldn't restore those. The only thing that still worked via Bluetooth was Freelink.

After seeing this post I e uninstalled Freelink and hey-presto, pairing to everything else is working again. Thanks again. (Phone is a OnePlus 6T).

[Mark J]

Tim.

Thanks for your input. I've reinstalled freelink and get the same pairing problems, when I force stop the app everything is OK. Not really a problem now I know what's causing it. A search on the web dose'nt come up with anyone else having this problem so I must be unique . It's probably down to the android system I'm running, it,s Xiaomi's own version MiUi.

[Tim Ballinger]

Sounds like a mix of issues that cause this problem then. I have actually deleted the FrSky link from my iPad anyway as apart from the novelty I could not find real use for it except for motor set up/testing and I can alwAys download it again next time I set up a model & motor.

tiim