Canon 600EX II-RT drops link- HELP!

[Phillyphoto]

Scenarios I have tried: 

Using Canon Transmitter ST-E3-RT as the master and (2) 600 EX II-RTs as slaves.

Using A 600EX as master and B 600EX as slave.

Using B 600EX as master and A 600EX as slave. 

I get the same result of the slave dropping link. The time varies. Sometimes it drops link in 4 mins, sometimes 10mins, sometimes 20 or more minutes. The only way to relink them is by turning everything off and back on.

All channels are the same. Yes, I have scanned for the best connection as well as every other channel and AUTO.

All IDs are the same. 

Not near a wifi-router or airport, I'm in a row home in Philadelphia. 

Using NiMh rechargeables and using freshly charged batteries for every test. Batteries are about 2 years old. 

I have spoken to 2 Canon service reps and neither of them has any idea what the problem is. I really don't have the money to spend on sending everything in for "repair". 

Any help is greatly appreciated, thanks!

[crlyhds]

Any issues?

[JimOsdale]

No problems at all. 

[crlyhds]

Thank you

[BillWayToday]

Since I own a spectrum analyzer I figured why not...  so I can say with confidence that 2.4GHz is crowded like Interstate 90 in Chicago at rush hour.  This is true even after I disabled the 2.4GHz band on my house router.  Some portable (not cellular) phones use an adjacent band (1.9GHz) and those signals are, in my case, exceptionally dirty. 

Canon uses 15 frequencies starting at 2.405GHz (Ch 1) and up by .005GHz to 2.475 (Ch 15).  Spacing is 5MHz which should far exceed the bandwidth of a (clean) digital signal. 

Using the "Scan" function is unlikely to be helpful unless you run it several times and find a consistently good channel (the spectrum analyzer solves that problem by "listening" over several minutes and accumulating the data).  Most of the interfering signals come-and-go and "Scan" captures only one instant in time which may not be indicative of your total RF environment.  You can emulate my SA by doing multiple scans.  

Why the digital data (4-digit code) would matter I have no clue but what-the-heck.  I'll change from my birthday to 9999 and say a prayer to the camera gods.  

Maybe this is a plot by Westcott to make us all change to continuous light.  

[JLCKJC]

Thank you for your testing and report. It further suggests that EMI in the frequency band is the issue with the Canon triggers. Why other manufacturers products work much better, and Canon's don't remains a mystery. And why Canon keeps introducing products with this weakness is also a mystery. To preserve my Canon investment for the time being I obtained a Godox trigger and three receivers to which my Canon 600EX RTs are mounted. This workaround works fine in the environments in which the Canon system failed to remain linked over and over.

[BillWayToday]

The fact that the connection drops upon interference is fine with me... AS LONG AS THE UNIT AUTOMATICALLY RESETS AND RECONNECTS.   To me, this is a software issue which should be within the power of the smart people at Canon to remedy.  Apparently not today (and tomorrow isn't looking any better).    

Meanwhile I'm trying an LED continuous light solution pending a possible Godox purchase.  I have FIVE Canon speedlites so any expense is times 5.  

[halocastle]

For those who don't know, Westcott also make speedlights/strobes that are RT (Canon radio) compatible (their FJ wireless system): I have no experience with them, just the gen 1 trigger (which I didn't care for).

As for the Chinese flashes, FCC part 15 requires devices to accept interference, "...including interference that may cause undesired operation."  I would suspect they are out of compliance.

[JLCKJC]

On the Westcott site they also mention that Canon users have reported dropped links using the RT system as reported in this forum. They even provide a link as I recall. Westcott does not guarantee that their emulation of the RT system is any better than the native Canon RT system. Also, regarding your FCC comment, I believe that part 15 is pretty vague in that it says it requires devices to "accept interference" but it does not explicitly say they should operate properly under the circumstances.

[halocastle]

One more point, the EL series speedlites are firmware updatable via newer camera bodies (recalls are expensive). If issue "x" can be fixed via firmware, then a fix could be in the works.  Canon just released the EL-10 to replace the 430EX III-RT so all of their current speedlites are EL series.

I've used and really liked the Yonguo YN622C flash triggers. They're transceivers so they do double duty and have a hot shoe and you can continue to use whatever TTL flashes you currently own.

P.S. Most of the "tips" concerning how to address RT issues came from the Godox forums (I know, since read them and posted here), so there is no panacea in the 2.4 world.

[tseager]

I had great success with the Canon system for years. Seven flashes and a controller, with lighting modifiers that matched. 

I could not get them to work for more than three minutes at a time, at which point I’d need to power cycle all flashes. 

I eventually moved to Westcott. More power, lower build quality, but they are 95% reliable, as opposed to 10%.