Icue - Rosco - Twitch ?

[pjc]

Hey out there,

Has anyone experienced a slight twitching in Rosco ICue mirror units? I have two, and both of them on this rig are constantly twitching. It is not the actual units as I swaped them out with new ones. Power..DMX ??

THANKS..

[Footer]

Check your DMX, make sure its terminated and check all cabling.

[gafftaper]

Off the top of my head...

Could be something weird in the power supply unit. Try swapping it out with another one.

Do you have other DMX units in addition to the I-cues and no DMX terminator? Or do you have I-cues on two or more power supplies without a DMX terminator? Could be reflections in the line. The I-cues don't need a terminator but if they are all alone on one power supply. However if the line goes from the power supply off to something else you could get some weirdness that way.

Is it real high quality 5 pin DMX cable running between the DMX out and the power supply unit? Cheap home made XLR cable conversions can do weird things.

[pjc]

Thanks for the reply,

All the cable is 'high quality', and the power supply is only running the two I-Cue units.

However there is no termination - I thought the I-Cue units did not require this. The DMX runs directly out of my board (Strand 520) on a 100' to the first unity, then to the second (25' run).

I will swap out the power supply later today, to eliminate that.

Thanks.

[gafftaper]

I'm not exactly DMX expert but it's my understanding that the system recognizes everything on that power supply as one DMX unit. So you shouldn't need a terminator. I have used two I-cues on one power supply with no terminator and never had a problem.

[MRlettherebelight]

Try terminating the dmx, and or swapping out dmx cables. Dmx problems can be a huge pain and hard to track down, I've had dmx porblems with dimmer packs that caused the lights to flash, which it you translate that into the way the i cue works would equal twitching. The dmx prob may not be at the power supply it could be up the line at a dimmer or something else.
hope this helps.

[Andrewr]

The DMX standard specifys termination for any cable run, regardless of length or number of fixtures. Yes you can get away with not bothering a lot of the time, BUT twitching fixtures is a classic symptom of an unterminated line. Try terminating the DMX, if that doesnt fix it you can then ring Rosco and gurn at them!

[Van]

I wholeheartedly concur with Andrews assesment. Twitching, in almost any Intelligent fixture, is best first addressed by looking at your DMX. You can look at other threads on here and find that I'm a DMX termination Nazi. If you don't have terminators at the ends of your runs you cannot move forward to any other trouble-shooting proceedures until you do terminate. Terminators are simple, cheap, and using them will only help you. The only problem I have ever seen, that was caused by a terminator, was when one was improperly or poorly constructed. I do not understand the great number of people in this business who still don't understand or get confused about terminations on DMX. $10.00 in parts can save you hundreds in man hours of running around pulling your hair out.

[Footer]

Because the units are 4 pin you will need a special terminator, I suggest this...http://www.internetapollo.com/Produc....aspx?pl_id=38

[lightbyfire]

I actually was about to post a thread about this when I saw this, we had exactly the same problem today, and we also traded out the I-cue but also the power supply, and we had a terminated dmx run. we ultimately decided it must be something in our shownet system, I wonder if it is inherent in strand DMX refresh rates? either way all of our I-cues have the same problem, it is very annoying.

If you figure out how to get it to stop please let us know.