[chippywat]

Starting around Sept 2018, I've had extreme range issues with FrSky transmitters and receivers. I've now tried three different transmitters each with three different receivers. I feel like I've tried everything I can think of, and I've searched for advice and not found anything that makes sense. At this point I'm wondering if there is some kind of radio interference in Waterloo Ontario that is affecting me.

I've been using a Hitec Optic 6 with an FrSKY DFT tx module with 4 different D6FR receivers for around 5 years and had no range issues up until around Sept 2018 flying at several fields in north west Waterloo Ontario. I often flew over 200m from the transmitter (sometimes over 300m) with no range warning issues.

In mid Sept 2018, I started having issues with range with multiple D6FR receives at multiple sites. I was getting rage warnings at less than 50m. FYI, I may not have flown for a month or more before this so I don't know exactly when it started happening. Given it affected multiple receivers, I thought the problem was likely the transmitter module, so I got a new FrSKY DFT tx module, and did a range test on my street and thought I got over 50m and was OK. Given there were trees, cars and lots of wifi, I thought not getting full range was likely OK. But I didn't get back out to fly until April 2019. I tried flying again in April 2019, and again, got serious range issues with multiple 5 year old D6FR receivers.

Thinking the problem could conceivably my Hitec Optic 6 (which was ancient anyway), I then got a Taranis Q X7S. I tried my 3 five year old D6FR receivers with this new transmitter and got serious range issues (less than 50m) at three different locations (my street, and two other fields - one with 100m of an office building, and one within 50m of a church). Note one time at one location, I got over 100m range with one of my D6FR receivers, but within a few minutes, got less than 50m with a different receiver. At other locations on a different day, even the D6FR receiver that got more range, got way less than 50m.

Given that this is failing with 3 different transmitters and 3 different receivers, the only things left I can think of are:
1) interference that affects multiple sites around over 3-4 km apart
2) maybe the D6FR doesn't work well with the Taranis Q X7S (that doesn't explain why it stopped working as well with two different FrSKY DFT tx modules)
3) maybe the D6FR is affected by newer WiFi protocols (such as ac?)

FYI, I'm doing range tests on the ground with:
i) a quadcopter
ii) a flying wing (Stryker)
iii) just a receiver with just a battery and single servo
In all cases there is no video transmitter or anything that should generate interference on the planes. The limited range is when the motor is not running, so it's not interference from the motor or speed control. The receiver wires are 5" long and spread approx 45 degrees, and I've tried different tx transmitter orientation. I've also tried 4AA rx battery, as well as 3 cell Lipo + BEC to rx power and verified my tx and tx are charged.

I'm at a loss. Any ideas?

Thanks and kind regards,
Ian

[cassat]

Well, its an interesting topic for sure.
I have the Hitec Eclipse 7 and the same DFT module
The only difference is that I have the V8FII receiver
Unfortunately, I haven't tried it yet but one thing I noticed was
that your modulation in the menu must be PPM and not QCPM. See page 14 of the manual
I am wondering how you get the low range warning? Does it flash or beep
on your transmitter?
Usually range issue is related to either the TX antenna or the receiver antennae and
not so much a crowded frequency bandwidth. The receiver antennae are a micro coaxial
connection on the PCB board so not actually soldered. They may be getting old.

[4*60]

Are you on the ground in range test mode????? If so 50 metres should be a good test. Trying to understand what you are describing.

You describe on the ground then you mention flying??

Maybe I'm just slow but I am confused.

[Cougar429]

I have been using FRSKY gear, both Futaba FASST and their own legacy ACCST setups for years now with rock solid performance. Did quite a bit of reading and there were no reports of issues at all so this is a new one for me.

Their ACCST is frequency hopping so theoretically any single source interference should not affect the link much. However, broad band comms such as WIFI or cell towers may be blanking a much wider spectrum. The latter seem to be sprouting like weeds.

Does the Tx or module have a "Range Test" option? That will reduce the signal strength.

It may be worth looking into flying at a club site where you have a more comprehensive comparison to different systems and if any problems at that location. If none and yours works well there you may have narrowed it down to site specific.

[chippywat]

Hi all,

Thanks for the feedback.

With the FrSKY DFT tx modules, by alarms I mean in full range mode the range warning chirping. With the Taranis Q X7S tx, by alarms I mean in full range mode an RSSI of less than 42 and spoken "range critical".

I confirmed my Hitec Optic 6 was in PPM mode. Note the control surfaces do move correctly at very short ranges, so I know the rx is bound correctly.

WRT to problems with the tx or rx antenna, I get what you are saying. However it doesn't seem that could be the problem given it happens with two different tx modules and a new Taranis Q X7S tx (all with different antenna), all with three different D6FR rx (all with their original antanna that worked earlier in 201.

All of the range distances are in normal full range mode. In range test mode, I get 1-5m, some minor difference depending on the which receiver and which location (consistent with range test mode giving about 1/10th of the full range).

Previously I got 200-300m with no alarms while *flying*. Since I started having this problem, all of the distances (less than 50m) are based on a *ground* distance test while the transmitter is in normal full range mode. The one exception is that with one receiver this spring I thought the range was OK and I *flew* to over 100m with no alarms. But that same receiver has had very limited *ground* range at multiple sites so I no longer trust it.

The D6FR rx is ACCST. I have a ready to fly quadcopter that uses 2.4GHz Futaba S-FHSS and it seemed fine on a couple of the same days and locations *flying* to around 100m.

Also, I tried a different site at least 4km away from the other sites. With one of my D6FR rx and my new Taranis Q X7S tx, I only got 10-15m in normal full range mode.

Unfortunately, I'm not part of a flying club, but I guess I could drop in on the local KW Flying Dutchmen and see if anyone uses FrSky and ask if they have heard of any issues.

Hopefully this clarifies my problems.

At this point I'm wondering if I should try getting one newer say FrSky X6R or X8R rx and see if the problem is the older D6FR rx.

Thanks again,
Ian

[stegl]

Ian , have you tried range checking with the ant. tips 90 degrees apart instead of the 45 degrees That you mentioned ? I can see maybe having a range issue with 1 maybe 2 receivers but with all of them ; I would start to suspect maybe the transmitter. On the other hand it might be the installation.... try posting some pictures of the receiver installation.

On another note , might be a good idea to join a MAAC club due to the stringent transport Canada rules coming into effect the beginning of June .

[cosmith]

I'm not at all familiar with the receivers your using, but I've used 3 different FrSky radios and just about every x series receiver available and have had exactly 0 range issues.

The only thing in common I'm seeing is that all the receivers are the same model. Perhaps try an x-series, or really any different receiver model to see if it helps. I'm thinking hypothetically you're running into some sort of issue that the D6FR is susceptible to. It seems like you've eliminated every other possibility...multiple modules, transmitters and different aircraft...the only constant is the receiver model.

This may interest you: https://www.rcgroups.com/forums/show...n-range-issues

[jsparky]

Hi Ian.. I see you live in Waterloo.. I have an X9D and a 12S that are known to be good working radio.. I would be willing to get together with you and do some range testing..

You didn't happen to update your radio firmware with EU firmware by chance.

regards jeff

[4*60]

Any conclusion here??

[jsparky]

Originally Posted by 4*60

Any conclusion here??

Not that I can see.. never heard from him. but I can put another poker in the fire..

Lately, both me and a buddy have been getting " low rssi " warnings. We both fly the X-12s and what is really strange is that we get the warnings in different locations.. for example,, my old hobbico.. I have seen me get a warning when I was a fair distance out from the field and get the warning as I pass over the field.. I would get a warning at one spot lets say,, so I would fly several more passes as close the the same spot and not get any warning, then next I would get one just as I passed over the field.. so again I would make several more passes over the same spot , and again no warning.. Would fly to the left and I would get the warning as I approached the field.. so turned around and flew to the right , got the warnings as I approached from the other direction but not as I passed over the spot from the other way.. WTF !!

This is not isolated to one aircraft , it has happened on several including my buddies planes..

So tried a new Rx with antennas in a different orientation ,, same results..

range check on the ground shows nothing.. So I recorded the logs to see.. the rssi looked very much the same as any other I have recorded..

Have checked the 12s against my x9d on a ground check , same results in signal strength. both radios are running the same 2.2.3 firmware..

My conclusion is that there is a latency problem in the firmware in the updating time it takes to check the rssi..