davidm wrote:
I'm going to be shooting some more this evening, and I'll experiment a bit with settings changes to see if I can come up with a more consistent way to cause it.
Well, it's been a while since I posted that. After trying a variety of things, I think I've gotten a little closer to understanding what's happening. At least in
my particular situation.
It has made no sense to me that I would start to have trouble like this, when nothing in my setup has changed (other than the firmware update, which didn't seem likely). So I decided to investigate potential causes that were external to anything in within my immediate control.
The condo that I live in at present is one of 12 units in a single building. We've had a fair amount of turnover lately in building tenants, so I thought there might be a possibility that there was more RFI in the local area from new wireless routers, cordless phones, and the like. I obtained a free utility that lets you see the various wireless networks and their relative strength via a graph (the utility is inSSIDer if anyone's curious). I was shocked to see how many networks showed up, and that at least one sometimes had a stronger signal than my own, even when I was in the same room with mine.
A little background might be helpful for understanding this next part: apparently the majority of 2.4GHz wifi routers these days come pre-configured to "channels" 1, 6, or 11 (at least in the US). Note that the use of the term "channel" for wifi routers implies a frequency assignment, and is distinctly different than that word's use for Cyber Commander/CSR devices. In my case, the majority of my neighbors are using channel 6. I was actually set to channel 8, which I had chosen at random several years ago when I first got the device. Something that I never knew until recently, is that selecting a single channel for wifi routers actually just chooses the
center frequency; the protocol apparently uses a range of frequencies centered on that one for actual communications. For routers set to "channel 6", this range is 2.426 - 2.448 GHz. Note that the CC/CSR+ frequencies range from 2.427 - 2.457 GHz. That little bit of headroom at the top of the CC range was nicely covered by the "channel 8" range (2.436 - 2.458 GHz).
At my location, there were no less than 4 routers assigned to channel 6 that my computer saw, and anywhere from 3-4 others at other channels at various times when I checked. Perhaps importantly, the strongest two signals at my location were a neighbor's at channel 6 and mine at channel 8. Those two "channels" completely cover the range of CC/CSR frequency settings.
At the very least, the 2.4GHz spectrum at my location is flooded with wifi traffic. I have no way to check for other devices (cordless phones, etc.). So there's no telling how much more is actually going on here. Perhaps the "noise" from all these devices is causing CC messages to get partially garbled in transit? Will a partially-clobbered CC message lock up a CSR+?
Sorry for the length of this, I'll now get to what I did that seemed to make a significant difference in things. I set my CC/CSRs to freq 12 (2.449GHz), which is the closest thing I could get to a low traffic area for the wifi routers in my area. I then changed my wifi router to channel 1 (2.401 - 2.423 GHz), so that it's range would be distinct from my high-powered neighbor as well as my CC.
After doing this, I spent about 30 hours over the course of several days shooting work in my usual fashion. In this time, I had only
1 instance of 1 CSR (out of four in use) getting locked up. Prior to these changes, I would estimate that I would have seen at least 10-15 based on more recent experiences.
I certainly can't say conclusively that local wifi routers jamming the airwaves have been the cause of the recent problems I've seen. But I do know that my issues got significantly better immediately after I switched my router and CC to non-overlapping frequencies. Note that I used these devices successfully for many months before this problem ever showed up, even with my router set to channel 8. For most of that time, though, my CC system was set to freq 5, which is just below the lower limit of wifi channel 8's range. I can only conclude that it has been the
combination of my router with all of the other ones in the building that seems to have "broken the camel's back". Perhaps the powerful one set to channel 6 is a recent addition; I have no way to know who it belongs to or when it first showed up in my building.
Hopefully, this will be a workable situation for me moving forward. At least if the problem comes up again, I know where I'll start investigating! And when I'm a bit more caught up on work, I'll set things back to the old settings to see if the problems come back with them. I'm too busy with shooting workload to do that right now.
These experiences are my own... your mileage may vary. ;)