Taranis X9E

[Martyn K]

If so would you like to share your experiences?

Martyn

[GONZO]

Check out this thread on the BARCS site **LINK**

[Martyn K]

Cheers Gonzo

Yes - I have been following it, Hence my request for info here.

Quite puzzled with that thread and I suspect some disinformation has been submitted.

Martyn

[Geoff S]

I have no intention of replacing my Taranis with the new model though I do prefer its appearance and clean layout (more like my old Mux3030).

I notice one of the Taranis X9E users had fitted a Multiplex module which seems odd. One reason I decided on FrSky when I converted to 2.4gHz was because of the cost of receivers (a transmitter is a one-off cost - receivers are not). Multiplex receivers are not exactly cheap. At least the IPD 35Mhz ones I still have weren't. not sure about the newer ones.

I agree, Martin, it's a confusing thread. It's not helped that it seems some of the contributors know each other in RL and are continuing discusions on line that were started face to face. Nothing wrong with that of course but it makes it more difficult to follow the thread for others.

Geoff

[MattyB]

The main reason Mike Evans (isoaritfirst) has fitted a Mpx 2.4 module is because he has experienced unexplained range issues on both his X9E and early Taranis when using the EU RF firmware; worryingly he only gets ~250m with this setup, far less than he did on the Int'l RF firmware. Mike I know is fastidious about his installs, so this is worrying - either there is a problem with the new EU RF firmware (I am still on Int'l myself, but I won't be able to do that forever given the legislation changes coming in June next year), or there are QC issues in recent units.

[Martyn K]

I have been on EU Tx module firmware on my 9D since about April but the late Feb release that has backward compatibility with V & D series receivers

That's why I am a bit puzzled with this thread - the Tx module firmware version for the 9D and 9E should be the same

Martyn

[GONZO]

As well as the links to other threads referenced in the BARCS thread there is another thread here **LINK** that starts on one problem(may actually be the same) and then goes onto the lack of range on FrSky FASST compatibles.

IMO from my reading of the various threads there seems to be three possible things going on, maybe in isolation, or in some form of combination.

1/ possible QC breakdown affecting FrSky products across the range eg new X9E, recently made Taranis, FASST compatibles etc.

2/ Product specific, X9E, problem causing lack of range.

3/ Question over the useabilty/suitability of the new EU compliant frimware in products sold in the EU (applies to FrSky protocol as well as the FASST)

The X9E and Taranis lack of range figures being quoted are from 250mtr to 300mtr ie no more than 1000ft.

[GONZO]

Had some more thoughts about this range issue. Soarers with large planes will fly at some distance from themselves and this would show up the issue. But, power flyers may not notice any range problems as they don't fly that far away. To check this I looked at my previous club and current club sites using Google Earth. Setting 1000ft as the distance from the flightline it is obvious that even large petrol planes are not flown at this distance in either club.

[Frank Skilbeck]

Posted by GONZO on 21/09/2015 16:54:46:

Had some more thoughts about this range issue. Soarers with large planes will fly at some distance from themselves and this would show up the issue. But, power flyers may not notice any range problems as they don't fly that far away. To check this I looked at my previous club and current club sites using Google Earth. Setting 1000ft as the distance from the flightline it is obvious that even large petrol planes are not flown at this distance in either club.

Gonzo, you are pretty spot on there, I have a GPS logger in my gliders, with my 3m stuff I max out at around 300m (1,000ft) height because it's getting uncomfortable to see, but with my 4.2m Topaze I've been over 500m height (1600ft), probably 700m straight line distance away. You can guess how far away the guys flying the 6m stuff go.

[MattyB]

Yep, I am inclined to agree guys - I think this is more likely to be about the new EU RF firmware offering less range than the previous versions, rather than being an issue with the X9E (or Taranis for that matter) itself.

This thread on FrSky's own forum is interesting - initially they admitted there had been a significant loss of RX sensitivity (and therefore range) on the EU firmware, then they went back on it at the bottom of the thread! Just another instance of the confusing and muddled comms that come from FrSky; they really need to work on being more open and transparent.

[Merlin spit]

I have had sevral lock outs on my taranis plus since doing all the latest updates.lost 3 models (

[Merlin spit]

lost faith in the radio altogether now as ive had double centring issues on the pots too that i had to replace.curently looking at options for the 30 so models ive got on frsky

[Geoff S]

Posted by MattyB on 21/09/2015 17:34:04:

Yep, I am inclined to agree guys - I think this is more likely to be about the new EU RF firmware offering less range than the previous versions, rather than being an issue with the X9E (or Taranis for that matter) itself.

This thread on FrSky's own forum is interesting - initially they admitted there had been a significant loss of RX sensitivity (and therefore range) on the EU firmware, then they went back on it at the bottom of the thread! Just another instance of the confusing and muddled comms that come from FrSky; they really need to work on being more open and transparent.

Another reason not to update my early version Taranis to the new EU spec. I updated the other software but not (I think) the RF section. It's some time since I did it. Is there a way of checking what version of the RF firmware is installed? The other one is easy.

I haven't needed to change any receivers to get them to bind but if I do, I'll rewrite the firmware to the international standard. The fact that 2.4gHz isn't an exclusive model control band was what made me hesitate to abandon 35Mhz in the first place. I had a feeling standards were likely to be updated as it got more and more popular. I think Multiplex's thoughts were similar but their late entry cost them market share, I think.

Geoff

[Frank Skilbeck]

There's a similar thread on here http://diydrones.com/forum/topics/frsky-not-so-free?id=705844%3ATopic%3A2088765&page=1# comments but interestingly he thinks he's tracked the problem down to the RF board being poorly soldered in the Tx and when it breaks down after a year or so the effect only shows up with the X series Rxs, seems strange to me that only one type of Rx would be affected though.

One thing Multiplex's late entry did though was allow them to develop their system to the new regs from day 1, rather than have to re-engineer it, so until the EU changes the regs again they should be in the clear..............................

Edited By Chris Bott - Moderator on 21/09/2015 21:56:08

[Chris Bott - Moderator]

That's a scary report you link to Frank, with photos showing that 6 of 7 pins at each end of the RF board have never seen any solder in their life. They'd been working by just touching and eventually caused this odd issue. I wonder if the D16 protocol uses one of those pins where other protocols don't?

I'd suggest that every Taranis should be checked for this issue, which is likely to be there if the soldering of those is a manual operation on the production line.

[Chris Bott - Moderator]

I've just checked a photo I'd previously taken of my RF board, and all 7 pins at both ends are fully soldered - phew!

[MattyB]

Posted by Geoff Sleath on 21/09/2015 20:34:32:

Posted by MattyB on 21/09/2015 17:34:04:

Yep, I am inclined to agree guys - I think this is more likely to be about the new EU RF firmware offering less range than the previous versions, rather than being an issue with the X9E (or Taranis for that matter) itself.

This thread on FrSky's own forum is interesting - initially they admitted there had been a significant loss of RX sensitivity (and therefore range) on the EU firmware, then they went back on it at the bottom of the thread! Just another instance of the confusing and muddled comms that come from FrSky; they really need to work on being more open and transparent.

Another reason not to update my early version Taranis to the new EU spec. I updated the other software but not (I think) the RF section. It's some time since I did it. Is there a way of checking what version of the RF firmware is installed? The other one is easy.

I haven't needed to change any receivers to get them to bind but if I do, I'll rewrite the firmware to the international standard.

You can do that for now, but not beyond June 2016 - here's why...

[Martyn K]

If this a D16 problem with x series receivers then it should be possible to prove by binding in D8 mode.

I am still bothered why this is considered an EU protocol problem. Again, it should be possible to eliminate by implementing the International protocol. I think a lot of these problems could be proven by comparing a working system with a faulty one and simply exchanging modules unt the fault moves. Basic fault finding techniques

martyn

[Phil Green]

I've not tested any X series receivers so I dont know if what he says about diversity is true, but I do know for certain that V and D receivers do switch antennas, you can see the ES02 select pin alternating. His suggestion that "... bind code holds target frequency info, it may be corrupted (by swamping) causing range issues..." sounds like tosh, bind packets are crc'd like any other and are decoded perfectly or not at all.

But the soldering thing is bad, very bad. And its not the first time:

[Mike Blandford]

My understanding is those two rows of pins are mechanical, electrical. The daughter board is, in fact, just the PCB from a 'normal' XJT external module. These only use the 5 connections at the bottom right of the picture above.

I find it interesting the opriginal poster on the DIYdrones thread says he unsoldered the two pins of the 7-way rows and lifted the board off. He should have needed to also de-solder the 5 'normal' connections as well. If he did so, then re-mounted the board, then he must have re-soldered those 5 connections as well as soldering the 7-way rows. As such, he hasn't 'just' soldered the 7-way rows as part of his 'fix'.

At each end, there are two rows of 7 pads. Most of these do NOT connect electrically to anything. Two connect to pin 1 of the 5-way connector (PPM/PXX signal), Two to pin 3 of the 5-way connector (Battery voltage) and Two (or three) connect to ground (pin 4 of the 5-way connector).

I also have access to the circuit diagram of the back board to which this XJT is solodered. These rows of pins are not shown on the diagram.

My conclusion is these rows are purely for mechanical positioning, and the electrical connections are via the 5-way connector.

Mike.

[Martyn K]

Posted by MattyB on 21/09/2015 17:34:04:

This thread on FrSky's own forum is interesting - initially they admitted there had been a significant loss of RX sensitivity (and therefore range) on the EU firmware, then they went back on it at the bottom of the thread! Just another instance of the confusing and muddled comms that come from FrSky; they really need to work on being more open and transparent.

I am a bit puzzled by this. I was under the impression that the only real difference between EU and International protocols was the requirement to listen before transmit. Apart from the fact that could delay (momentarily) a packet being sent, it should not have affected range.

According to the FrSky thread, the EU protocol transmits packets at a faster rate, this means that the bandwidth requirement for the receiver increases resulting in a loss of sensitivity - down by about 14dBm - which is quite significant.

I always considered that a good rule of thumb for a state of the art transceiver system would have a range of at least 2km. That's just an assumption, reality is that it may be considerably more than that and is dependent on aerial orientation etc.

For every 3dB drop in sensitivity equates to a 50% received power loss - please correct me if I am wrong, so working backwards, 14dBm is almost 5 halvings of power - so the maximum range therefore drops from:

2km/2 = 1km/2 = 1/2km/2 = 1/4km/2 = 1/8km/2 about 70m

Even if the range of an International system was increased to 5km then the max EU range would still only be 350m - which is marginal for power flying - inadequate for gliders.

I do not believe for a moment that the -90dBm sensitivity quoted is accurate or we would all (on EU spec) be falling out of the sky.

Boffins - what are your thoughts?

Martyn

[Biggles' Elder Brother - Moderator]

I'm not an expert in this area but I would suspect that power relates to distance as an inverse square law - not a simple linear effect as you have it Martyn.

BEB

[Martyn K]

Thanks BEB, I'll go and check although someone like Phil Green would probably give a more authoritative response.

M

[GONZO]

You can comply with the new EU regs in other ways besides adopting LBT. eg :- Leave everthing as is but drop o/p power from 100mW to 10mW(ETSI EN 300 328 V1.8.1 section 4.3.2.1); make changes so that the MU(Medium Utilisation) is 10% or below(ETSI EN 300 328 V1.8.1 section 4.3.2.4). The second option of reducing MU would appear to be what FrSky have done. I would surmise that it was the easy option(possibly the only option with current hardware) over LBT

BEB correct, twice(2x) the distance requires four(4x) the power in an ideal theoreticle case.

So, if I drop the Rx sensitivity by 6dB(6db equates to a factor of 4) I would halve its potential range. Drop it by a further 6dB and I would halve that range again. eg 1.5Km range with starting Rx, 750mtr range with Rx that has 6dB less sensitivity, 375mtr range with Rx that has a further reuction in sensitivity of 6dB. Now to my mind that would give a range of about 250mtr to 300mtr for a Rx, with a starting range of 1.5kM, that had had its sensitivity reduced by about 14dB, funny that eh.

[IanR]

Yes, funny.

(What's he on about?)