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Radio Equipment => UHF Systems => Topic started by: dogzilla on June 27, 2012, 08:36:26 PM

Title: Major EzUHF issue...
Post by: dogzilla on June 27, 2012, 08:36:26 PM
I've got a major EzUHF issue that I've been trying to diagnose...

You can see in the attached video the symptoms. Momentarily I lose all control, uhf goes into failsafe.

It has happened 100 meters away, I almost crashed 3 times today before I got it back on the ground, all within LOS distance.

I've:

Bought a new RC TX.
Bought a new EzUHF RX Lite.
Got replacement EzUHF TX.
Tried standard firmware and UK firmware.

No difference. Same problem. Now someone has suggested that because I live in London there is alot of interference. Can I really be getting failsafes at 100-200 meters? Even with the 459 UK firmware? Could it be something on the plane like my BEC cutting power to the RX?

I'm stuck and I'm getting really annoying now, this has been plaguing me since the day I got the UHF system.

private link ezuhf issue (http://www.youtube.com/watch?v=T0sF2o12P8M#)
Title: Re: Major EzUHF issue...
Post by: Coyote on June 27, 2012, 09:02:57 PM
Your RSSI and bad packets show the link seems fine, but alarm appearing is showing the link itself is fine, but something is either shutting down or blocking it.

I would look at BEC shutdown, Vtx frequency clash, or external interference
Title: Re: Major EzUHF issue...
Post by: Njoro on June 27, 2012, 09:41:22 PM
Hi

"have you tried powering the RX from a separate lipo and liner power regulator"?
Title: Re: Major EzUHF issue...
Post by: c0nners on June 27, 2012, 10:59:15 PM
Quote from: dogzilla on June 27, 2012, 08:36:26 PMI'm stuck and I'm getting really annoying now,
not much help from me... but stick with it fella. it will all come good. /fingers_crossed
Title: Re: Major EzUHF issue...
Post by: lemonsorbie on June 28, 2012, 01:46:58 AM
Hi Dogzilla,

Are you using a GoPro with the EZUHF. The GoPro is a source of interference with EzUHF and will cause servos to stall/stop working.

Steve
Title: Re: Major EzUHF issue...
Post by: dogzilla on June 29, 2012, 12:05:19 AM
Yes I have a GoPro2 strapped up front.

It's deffo not that, it happens when the GoPro is off.

Anyway ended up crashing the Z2 today. Failsafed as I was coming into land, it's very windy at the moment and the motor obviously cut out. Stalled just as it came out of FS, too late to recover it.

Which BTW... the Z2 is a monster when it stalls. It just flips right over.  So that's two Z2's dead. It's so bullshit this UHF business has caused me more problems.
Title: Re: Major EzUHF issue...
Post by: lemonsorbie on June 29, 2012, 07:06:01 AM
Hey buddy,

Sorry to hear about your Z2 and UHF issues. Had to ask about the GP as this is definitely a problem concerning UHF compatibility and servo interference.

Sorry I couldn't help you out.

:(
Title: Re: Major EzUHF issue...
Post by: Coyote on June 29, 2012, 03:02:47 PM
Can you list what setup and equipment you have on board so we have more details to go off
Title: Re: Major EzUHF issue...
Post by: markvanhaze on June 29, 2012, 11:04:12 PM
Check the position of the trimmer on the EzUHF Tx. It has a flat side which should be pointing in the direction illustrated in the attached picture. If it isn't use a small screwdriver to make sure it does, turn it clockwise, not anti-clockwise. This sets the RF output power. If not set correctly you get abysmal range.
Title: Re: Major EzUHF issue...
Post by: Peter on June 30, 2012, 02:22:34 AM
I've seen similar drops outs and found changing to a dipole antenna helped.  Also found it useful to run some range checks using minimal electronics e.g. only battery, Bec, RX, single servo and VTX.   

http://www.terranova.net/~winger/RCVideoStore/DragonLink/Antennas/VerticalDipole/VerticalDipole.htm (http://www.terranova.net/~winger/RCVideoStore/DragonLink/Antennas/VerticalDipole/VerticalDipole.htm)
http://www.rcgroups.com/forums/showthread.php?t=1159968 (http://www.rcgroups.com/forums/showthread.php?t=1159968)

Title: Re: Major EzUHF issue...
Post by: dogzilla on July 28, 2012, 07:50:29 PM
I'm really close now to ditching the EzUHF... and I guess UHF all together.

I put together a new Skywalker with a halfwave dipole with my EzUHF Lite RX. Got the same glitches at my usual field, so I drove 28 miles East to here : http://goo.gl/maps/ZlVj (http://goo.gl/maps/ZlVj)

Now unfortunately I live in the South East of England, there isn't that much pure open space. So this was the best I could do without driving for 3-4 hours.

And yes still getting the same glitches, still within LOS range. (100-200 meters range)

To go back to what has changed since the first time I got these glitches:

Two RC controllers
Two EzUHF TX
Two EZUHF RX. (Lite + Diversity)
Tried Monopole and Dipole, tried sander style and active robot commercial antenna
Two different 433 Antenna TX antenna, one Nagoya and one Diamond.
Tried UK 459mhz and stock 433 Firmware
Has happened on 3 different airframes, 2 Z2s and one Skywalker
Different ESCs, different UBEC, Different Servos
Two different FPV cameras.
With and without GoPro.
Tried shielding VTX cable with cat6.

I've tried flying in different locations and even driving 28 miles East. So basically if my UHF system does work, the only way I can rule out interference is driving to Wales. And what's the point in a system that you can't use in your regular flying spots.

So yeah.... I'm pretty close to getting rid of this.

Maybe I have to go for a FRSKY 2.4Ghz system? RangeVideo tout it as LONG RANGE. It definitely seems achievable to get 2-3km out of it.
Title: Major EzUHF issue...
Post by: Zeeflyboy on July 28, 2012, 09:57:38 PM
No it's complete nonsense... It can't be environmental interference at this point.

It really is just bizarre... You've covered everything. Do you live near someone with a known functioning EZUHF that would be willing to help you trouble shoot using their known functional equipment?

I mean, it's not beyond the realm of possibilities that you got two duff EZUHF tx in a row...
Title: Re: Major EzUHF issue...
Post by: dogzilla on July 28, 2012, 10:22:17 PM
Quote from: Zeeflyboy on July 28, 2012, 09:57:38 PM
I mean, it's not beyond the realm of possibilities that you got two duff EZUHF tx in a row...

Possibly but the second TX was sent by Sander from Immersion and pretty sure it's a known working one.

The only thing that hasn't changed is my VTX type, but as far as I know the 5.8 VTX don't interfere with UHF, and I've tried two of the same type.

The reason why I mentioned local interference is because someone came onto another post I made on another forum and said that he has similar issues around London, but no such problems at the coast. I entertained the idea because my main flying site is Hackney Marsh which is less than 1mile from the Olympic site.

But I drove 26 miles east, surely.... surely that's open enough to be usable. or so I thought.
Title: Re: Major EzUHF issue...
Post by: pk-surfing on July 28, 2012, 11:07:07 PM
I don't have EZUHF (I use Scherrer LRS) but if the EZUHF has a micro power mode for doing a close range check then I would be pacing that out.... with no FPV gear connected up at all (cams, Vtx, osd etc etc), to check out range with only the EZUHF in use.

Then do the same with the FPV gear switched on and see if there is a noticeable difference.

Let us know what sort of distance you get with this ?

PK
Title: Re: Major EzUHF issue...
Post by: papa_lazerous on July 29, 2012, 01:20:42 AM
I have seen across all the forums lately that allot of people are having issues with EzUHF.  It seems early units are ok but the more recent mass produced units have had serious QC issues.  Ofcourse you will never get a straight answer from ssassen as he likes to mock and flame his customers on the most part.  I have flown on UHF extremely close to the pointer on the google map you linked to and it was fine (I was within half a mile)
Title: Re: Major EzUHF issue...
Post by: dogzilla on July 29, 2012, 02:19:20 AM
Quote from: papa_lazerous on July 29, 2012, 01:20:42 AM
I have flown on UHF extremely close to the pointer on the google map you linked to and it was fine (I was within half a mile)

Bugger :( As it happens I've gotta drive south today so I'm gonna take the plane and give it one more try. Otherwise I don't know what to do, maybe swap the EzUHF for a TSLRS ? :)
Title: Re: Major EzUHF issue...
Post by: ssassen on November 05, 2012, 08:54:57 AM
Quote from: papa_lazerous on July 29, 2012, 01:20:42 AM
I have seen across all the forums lately that allot of people are having issues with EzUHF.  It seems early units are ok but the more recent mass produced units have had serious QC issues.  Ofcourse you will never get a straight answer from ssassen as he likes to mock and flame his customers on the most part.  I have flown on UHF extremely close to the pointer on the google map you linked to and it was fine (I was within half a mile)

Serious QC issues? And you arrive at that conclusion because? And I don't give straight answers? You must be confusing me with someone else, I'm a straight shooter and always tell it like it is. Whether that's the answer people would like to hear is another story though.
Title: Re: Major EzUHF issue...
Post by: WSWhitby on November 11, 2012, 11:53:47 AM
Quote from: ssassen on November 05, 2012, 08:54:57 AM
Quote from: papa_lazerous on July 29, 2012, 01:20:42 AM
I have seen across all the forums lately that allot of people are having issues with EzUHF.  It seems early units are ok but the more recent mass produced units have had serious QC issues.  Ofcourse you will never get a straight answer from ssassen as he likes to mock and flame his customers on the most part.  I have flown on UHF extremely close to the pointer on the google map you linked to and it was fine (I was within half a mile)

Serious QC issues? And you arrive at that conclusion because? And I don't give straight answers? You must be confusing me with someone else, I'm a straight shooter and always tell it like it is. Whether that's the answer people would like to hear is another story though.

Hi ssassen and all,

Why not put "actions where typing is" and offer to take back some of the equipment that dogzilla has and check it out to reassure others who may be contemplating buying UHF gear.
Just a bystanders who intends to try UHF in the near future.

Regards

John