Paul C. Buff, Inc. Technical Forum

Hi guys, first post here.
I inherited a Broncolor Impact 21 monolight from my father and tried connecting it to one of my CSRB+ receivers but I can't get it to fire. I tried both the test/dump button on the receiver and via trigger. Connection is via 6 in. sync cable with 3.5 in. connectors on both ends. The kicker is that the strobe fires properly when I connect it directly to my camera via sync cable, so I know it's properly receiving the sync pulse.
Any help? The 21 is pretty ancient, but I thought it would be useful as a rim light.
Thanks, Jon

The Cybersync is a polarity sensitive. You have to build up a cable to flip the ground/power. Same is true for firing a Speedotron pack w/ a cybersync. I had to build a cable for one of my friends...

Perfect! I'll give that a try.
Thanks a million!
Jon

P.s. if this happens with various other brands of lighting, I would think PCB would sell a crossover cable.

The polarity is likely the cause. However, when this usually happens, it is with a HH style sync connector. Audio style connectors are rarely reversed, but it has happened.

Well, I made a 3.5mm crossover cable and that didn't work, so I'm kind of out of ideas now. The Bronc fires just fine when hardwired to my camera, it just won't trigger off the CSRB+. I'm using the M/M 3.5mm short cable that came with the receiver.

Any more troubleshooting ideas that I might try?

P.s. - TS, thanks for the reply. Your comment re: HH cables getting reversed made sense. Unfortunately, I don't believe that's the case here.

Are you sure the cable you are using is a functional cable (i.e. no shorts or breaks in the cable)?

Have you tried a different receiver?

Is your cable mono or stereo?

While it is almost always a polarity issue, it could be the receiver does not close the circuit long enough to trigger the light, which requires a longer close time.

The cable is functional; it works fine on my AB800.

I haven't tried a different receiver, but will do that this weekend. However, the receiver that I did try with the Bronc works fine on my AB800.

Cable is mono.

I think your last statement best fits the facts so far. Also, the Bronc fires just fine when attached directly to my camera, so I know it's able to process a sync pulse. Is there a common standard for a sync pulse duration? (Even if there is, I don't have a way to measure it...)

No, there is no common standard gate time.

Success!
I decided to start all over again from scratch to make sure I hadn't missed anything. Bought a new 3.5mm sync cable, rewired it for reverse polarity and presto - it worked! Not sure why it didn't work earlier, although I suspect my soldering skills are sorely deficient.

Well, almost success. Now, with my AB800 on channel 1 and the Bronc on channel 2, I can fire the 800 singly using my Commander, but when I try to fire 2 only, it always fires both 1 and 2. IOW, the 800 acts like it's a slave. Tips?
Tks, Jon

First, congratulations on getting this to work!

Next, be sure something is plugged into the round sync jack of the Alien Bee. This locks out the slave eye. Simply having the square RJ11 will not do this.

Also, make sure CH1 is defined as ABxxx and CH2 is defined as OTHER>MONOLIGHT (actually, it can be defined as anything, as long as it is defined. But you may as well define it correctly). If an active channel is not defined, but used, you can get unintended firing of other channels.