FliteFest East 2017 - Radio Issues

casedog21

New member
I just got back from #FFE2017 and again it was a great experience. This year we had two new guys with us that hadnt been before and they had a great time as well.

I noticed that there seemed to be a lot of people, including the five of us that had radio issues at some point during the event.
All of us had brownouts at some point. A few of them were recoverable but most were not.

This also happened at our flying field a few weeks ago on two separate occasions. We noticed that every time we went flying there was someone either in our group or other pilots around us that had a brown out. It was a mix of park flyer receivers and full range receivers in our group.

I personally have a hitec aurora 9x and up until 2 weeks ago I have never had a brownout on it. The brownouts that I had I was luckily able to recover each time. I know its still in the 2.4 band but it is supposed to frequency hop.

At flitefest I had 3 brown outs. 2 of them were at night. One was during the day. Both were parkflyer receivers. All were in a reasonable range. 1 of the night flights, I was one of 3 people flying. It happened twice that night.

Just trying to sort it out. Is there a new telco service popping up everywhere that is broadcasting on 2.4?
I wish I had my spectrum analyzer with me so I could have taken a look at the signal/noise while I was out there both at my home field and at FF.

I have full range receivers in most of my gear and they did not have a problem. I want to say that may be the problem but everyone else in my group has full range receivers in most of their planes and are flying spektrum radios.

Any ideas?

Thanks for any input.

-Casey
 

Winglet

Well-known member
Interesting you mention that Casey. A person the from the FCC showed up at our club field about a month ago and wanted to interview us about any interference we had received on 2.4. They were trying to track something down that they suspected was originating about 18 miles to the west of us. Yes, we are getting hit from time to time.
 

casedog21

New member
Interesting you mention that Casey. A person the from the FCC showed up at our club field about a month ago and wanted to interview us about any interference we had received on 2.4. They were trying to track something down that they suspected was originating about 18 miles to the west of us. Yes, we are getting hit from time to time.

I will scan that band at our field next time I get out there. It is very strange.


-Casey
 

97tj-neil

Member
I flew Thursday, Friday, and Saturday from the time my volunteer shift ended around 11:00 until 5:00 or 6:00 pm, about a half dozen to a dozen flights each day. I use a Spektrum DX6 and Lemon Rx running DSMX. I had not one brown out this year, even during the combat sessions. During two of the busiest combats I flew until my battery was exhausted - well over 5 minutes.

All of the Spektrum brown outs that I heard of were related to Orange Rx.
 

LitterBug

Techno Nut
Moderator
Copied this from another post I had which covered more than just RF:

I personally never had an issue with control signal loss while flying any of my Quads, Hex, or Tricopters on the east end of the field. I'm flying with a Spektrum DX8(V1) and DSMX 11ms protocol. Most of my RXes have diversity and was flying both LemonRX and Spektrum receivers. I did a handful of LOS quad flights just out from the build tents, with protected prop frames, mostly after dark, and with lights for visibility. Also Flew one of the Owls with the big spider in the Combat 12:30PM sunday. Flew my Owl frame with a non-diversity RX covered by a big spider at the center and east end of the field with no problems too. Only real RF issue I had was with FPV signals getting stomped on by people powering up VTXes off the flight line, not in the FPV areas, and without checking that the channel was clear BEFORE powering up. Anticipated this because it is difficult to manage at such a large event, so I focused more on LOS flight. Also kept my VTXes unplugged at all times except when getting ready to fly FPV. Made sure we unplugged any VTXes on builds/repairs that I was helping work on in the build tents too. Did get a handful of FPV flights early one morning with my Hellbender, AWK210, and Krieger frames. I wanted to test setting up the diversity on my goggles with two directional patch filters pointed tword the field, but never got around to it. Think that might have helped as I think that my Goggles were switching to the Omni antenna when I would get far enough away that the Omni signal from the stomper was stronger than my signal hitting the patch. The Race tent at the west side of the field had diversity with dual direcitonal antennas configured like that, but never got a chance to fly at that end of the field.

Cheers!
LitterBug
 

rockyboy

Skill Collector
Mentor
I never had a loss of control the entire event - I flew 10 batteries on Saturday, in all the combats, and had a nasty crash by the well - but it was pilot error, not control issue. I was using a Taranis with a mix of FrSky full range receivers, and LemonRx bound in DSMX mode.
 

tamuct01

Well-known member
All the problems I heard of were Spektrum and OrangeRx related. I personally lost control of a Bloody Wonder and crashed with a DX6i scavenged Spektrum module in my Taranis and an OrangeRx 6ch receiver. All other flights used FrSky and had zero issues.
 

PsyBorg

Wake up! Time to fly!
I had inquired why there were several areas that seemed like "dead spots" for certain gear. From the people I was having the discussion with there were two specific areas that had these zones on the field where strange radio behavior was very repeatable. The two specific areas were center main flight line just behind the Flite Fest signs and then further to the right about 30 or so yards up the field.

Some of the discussion pointed to gear used and then several people who know the area brought up the irrigation system that is out in that field and the amount of metal in the ground specific to those areas. I do not use the gear commonly associated with the brown outs nor do I know about the area so I can not confirm any of this but this was a discussion that was had in the build tents after several of the combats when I was on shift helping people.
 

JimCR120

Got Lobstah?
Site Moderator
I hadn't considered a brown out for my tricopter crash but now think it is a possibility. Mine happened on the far right side of the field and back fairly close to the corn.
 

LitterBug

Techno Nut
Moderator
I have a handful of SDR Dongles that could be used for monitoring but can't remember if I currently have one that works up to the 2.4GHZ range. One of the things I'd like to do is create a flying RF heatmapper. Have a couple different frames that I could use as a platform. Might be an interesting side project to work on and I'll throw all the details into a build thread.

LB

EDIT The unlicensed 2.4GHZ ISM band (2.400GHz to 2.4835GHz) used by modern RC TX/RX systems is shared with WIFI, Bluetooth, and several other protocols. Spektrum uses 79 1mhz wide channels, WIFI has basically three 22mhz wide channels, and Bluetooth has 40 2mhz wide channels (37 data and 3 advertising). It's plausible that some of the interference could have been caused by mobile wifi hotspots, Blootooth streaming, etc... It's best to use the newer channel hopping protocols such as DSMX than the older protocols that pick a channel or two and stay there. (like DSM2)
 
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Tench745

Master member
My friend and I found that at the east end of the field, about even with the eastern most gate of the FPV course no one was using, there was a pretty definable dead spot. There was a similar dead spot just east of the fabric runway on the main flight line. These dead spots seemed to run in radiating lines at a semi-regular interval from some point south of the field. Our best guess was the radio tower to the south. It was also suggested that that tower talked with the tower to the east, sending packets of information in "burst mode" so that these dead spots were not always active. This largely conjecture, but the dead spots my friend and I personally found in the field while flying were very defined.
 

CrashRecovery

I'm a care bear...Really?
Mentor
There has always been issues around the oil pump at the west end of the field. As for the rest of the field I don't know. The issues seemed to come and go. If you watched my radian fly live stream you saw one plow into the ground because of a brown out. That was on the east end of the field. Maybe next year if this happens again we can get Alex (IBCrazy) to scan the spectrum with his gear and maybe shed some light on the subject.
 

PsyBorg

Wake up! Time to fly!
That's not a bad idea. Getting a map of the area for any permanent dead zones could help a lot of people using older gear that seems to have problems more then newer gear.
 

casedog21

New member
The east side by the field straight out from the end of the runway is where we lost three planes. I like the idea of mapping the signal. I have some sdr's that reach up into our radio band.