Paul C. Buff, Inc. Technical Forum

I have a setup with 4 csr+ attached to ultra flashes.
I'm controlling the csr+ with the cc
My camera is firing with a cst

I created cc groups with one flash in each (to be able to fire only this flash with the cst during setup), I have groups with two flashes, and a group with all four (equivalent to the all setup in my case).

I've noticed some unreliability in at least one of my csr+. After firing a few times, the channel of this csr+ is turning red in the cc (despite using the refresh button) and I can't fire this csr+ either from the cc or the cst. The led on the csr+ is still flashing normally.
The only way to get this csr+ responding again is to unplug it from ac then plug it again.

I've had the same issue at least four times in the last month, but I'm not sure that it was with the same csr+. I've now marked it to try to debug more in the next days.

Is there something I'm doing wrong here? Could it be a rj cable problem (I did not moved the strobe nor the cable before it stopped working)? When the channel in the cc is turning red does that mean a radio problem between the csr+ and the cc or could it be also a csr+/strobe communication issue?

You said the LED on the CSR+ is still flashing normally, please expound. Does it blink red when the light fails to fire, or continue to blink green steadily?

are the lights plugged directly into the wall, or are you using a surge protector or extension cord or anything else between the power cord an wall? Try a different outlet on a seperate circuit. Bad grounding can cause odd things such as this to happen.

The light is plugged directly to the wall outlet with the oem power cord. This outlet has a proper grounding and I've also checked that neutral/live were not reversed.

I'll have to wait anyway for the same issue to happen again to try to troubleshoot more.

Try cleaning the RJ11 contacts. Over time, there may be a build up of dirt/dust. Also, is there anything else on the circuit like a refridgerator, air conditioner, etc? What about a dimmer switch?

It happened to me again today, and I was able to check more stuff.

Setup this time:
double wall socket A - one csr+/ultra directly plugged to it, two csr+/ultra plugged through a short heavy duty extension cord with dual output.

double wall socket B (could be on the same circuit, but I'll have to check on that) - one csr+/ultra directly plugged to it.


I was shooting without troubles with all strobes fired from the CST, or metered from the CC.
Then the three strobes on A stopped answering. The CC showed a red outer box while doing a refresh. No firing of these 3 strobes from either the CC or the CST. The strobe on B was still answering properly to remote control/fire

All three csr+ on A were still flashing slowly green as usual.
Pressing the test button on these 3 CSR+ was firing the strobe properly.
Removing the RJ11 (fired the strobe) then replugging it was bringing the strobe model lamp back to its previously set level.
Switching off the strobe, then on again was bringing the strobe model lamp back to its previously set level.
However still unable to remotely fire them.

The only way to make the CSR+ respond again was to unplug it from the AC, and replug it. When doing that only the one unpluged/repluged responded (to CC/CST), while the other two were still in the unresponsive state and needed AC unplug/replug.

The only stuff working at the time it happened was my A/C but I'm not sure that it was not on already before. Here in South Florida, the A/C is working almost all day long, and my strobes were on for a few hours already, then it was definitely not the first time they see my A/C switching. Also the A/C is not on the same circuit breaker and if the EMI is coming from it, then I should have the same issue on the other strobe connected to the other wall outlet. The fridge was off, no lights on, and I don't have dimmer as I switched to halogen a few years ago. I have some X10 remotes for some lights but none of them was in use at that time.

As an RF engineer I have a good general knowledge of EMI and RFI and I can understand why not everything can be filtered out by the CSR+ filter block.
But it's not a complete freeze up from the csr+ microcontroller as the strobe still can read its level settings from the CSR+ when powered on/off. Then would it be a problem only on the radio module part that would need a reset? Shouldn't the microcontroller have a watchdog to reset the radio module when needed?

Do you have all receivers set to a different channel? This would include any CSR+'s plugged in, but not on a light that is powered on. This would also include any CSRB+'s on, even if not connected to a light.

Have you tried different frequencies? If not, try a frequency well seperated from teh current one (i.e. if using freq 2, then try freq. 11).

All CSR+ are on a different channels. I have also two CSRB+ on different channels that were off during that time.

I've shoot all this morning with exactly the same setup as yesterday and the incident did not reoccur.

I'll try to change all my setup on a different frequency to see if it's happening again.

But I would like to understand the cause of this problem.

This is the first time we have heard of this type of situation where they will act fine, then just quit being responsive even after a power reset. It would be really hard to say right now exactly what is going on. Once we see what changes are made so that they do not continue happening, we may have a better idea. Please let us know what you find!

After a full power reset (AC disconnected) they are working again.
It seems to be radiated by the AC (as the 3 units on the same power outlet quit at the same time), but what is strange is that the dialog between the strobe and the CSR+ was still ok. Only the radio link between the CSR+ and CC/CST was down.

so you are comletely unable to adjust anything when this happens? If you unplug one light and leave it unplugged, do the other lights start responding?