Why are my lights flickering?

[Stevens R. Miller]

Well, someone appears to have worked on it today. At the request of an assistant principal, I sent him a detailed description of what I know, emphasizing that the PRE10A could be the culprit. When I got there Friday night, the PRE10A no longer did anything, having apparently been disconnected from the rest of the system. I observed no flickering throughout a three-hour rehearsal. We've gone long periods with no flickering before, but never three whole hours. I don't know who did what, but it does appear that the PRE10A is no longer part of the system or, at least, that it is no longer powered.

I have read repeatedly that improper termination causes lights to go wacky, mostly because DMX receivers get confused about which levels are assigned to which channels due to reflections. Since we never see the problem when all levels on all channels are at zero, but do see it when even one channel is at full, I can easily believe that we have a termination problem. If removing the PRE10A solves that, I can live without the device.

Here, by the way, is a picture of what it looks like to use a mix of DMX and Stone Age lighting gear, when you have to cobble up an independent lighting system after the school's system fails you:

That's my lighting team-leader, MC, at the command desk. She's more artist than engineer but, in case she sees this, I'd like to say she has been as much of a trouper as anyone ever could be in dealing with this nonsense, and she "plays" those boards you see in the picture like a virtuosa (when I can get them to work ).

 

[Les]

I love that you call it 'stone age' when it's not too far off from their current offerings! Really hard to beat those two-scene presets for simple control of a few dimmers.

 

[microstar]

Stevens, you might tell your new friend, the assistant principal, that he should consider sending the PRE10A back to Fleenor for testing/repair as they usually charge only $30 plus return shipping to fix their out of warranty products. Of course it could be faulty installation too.

 

[Stevens R. Miller]

I love that you call it 'stone age' when it's not too far off from their current offerings! Really hard to beat those two-scene presets for simple control of a few dimmers.

Yeah, "Stone Age" might be a little harsh. It certainly is more sophisticated than the stuff we had in my college days, which looked something like the picture below. It's just not what we expected to use and lacks the friendly graphical interface our software console provides. It also suffers by comparison when sitting next to the computer on that desk. If it were all we had, we'd actually be in pretty good shape. One adapts to the resources one has, after all.

My crummy Chinese lights just showed up. I'll give them a spin and report back here.

 

[Stevens R. Miller]

Stevens, you might tell your new friend, the assistant principal, that he should consider sending the PRE10A back to Fleenor for testing/repair as they usually charge only $30 plus return shipping to fix their out of warranty products. Of course it could be faulty installation too.

It's puzzling that it is still in the cabinet, just left unpowered. I mean, if I were the person who disconnected it, I'd have taken it out entirely for just your reasons. Perhaps the idea is that we're supposed to tell them if the problem went away and, if not, they'll just assume the PRE10A is a good one and, eventually, reconnect it.

And here is yet another example of how frustrating this all is for me: Someone made a significant change to the system, yet no one in my company has heard anything about it. None of us "lighting people" (as our director calls us) did it. No one has told any of us who did it. The assistant principal hasn't contacted me, even though I wrote him a detailed problem report yesterday morning (before, I assume, anyone came to work on it). I'm guessing the contractor showed up, told someone in the front office, "I'm here to work on the auditorium lights," and staff just let them in. Maybe an hour later, with the PRE10A disconnected, that person went back to the front office and said something like, "Okay, I made a change. Have them let me know if that fixes it, okay?" Staff probably said, "okay," and forgot that he was ever there, with the assistant principal never knowing anyone did anything.

I'll send him an e-mail and ask, but I had given him my phone number and he had said the school would call me when and if a tech came. I work at home and can be there in 20 minutes.

Art is about suffering, I guess.

 

[TimMc]

@Amiers Perhaps I've missed your point. To my limited knowledge, the alternative to aging is death. I'm still going with aging as the better alternative.
Toodleoo!
Ron Hebbard.

A few years ago I had an appointment with my doctor to discuss some aches, pains and other body-mechanic stuff. After listening to my complaints I asked her what the proper course would be. She looked at me and said "I could order a bunch of expensive tests your insurance won't cover, they'll come back negative because there's nothing wrong with you. It's just that you're not 19 any more."

The closer to 65 I get the more I'm saying "I'm too old for this crap, where's the FNG?"

Edit ps: I see the forum software has automatic word-nanny replacements...

 

[BillConnerFASTC]

You want stone age? This is a little closer:

My high school where I started working backstage in 6th grade - maybe because of light board - wasn't so old - more like:

 

[JohnD]

A few years ago I had an appointment with my doctor to discuss some aches, pains and other body-mechanic stuff. After listening to my complaints I asked her what the proper course would be. She looked at me and said "I could order a bunch of expensive tests your insurance won't cover, they'll come back negative because there's nothing wrong with you. It's just that you're not 19 any more."

The closer to 65 I get the more I'm saying "I'm too old for this crap, where's the FNG?"

Edit ps: I see the forum software has automatic word-nanny replacements...

Last century when I had my coronary adventure I asked my primary doctor about coffee, caf or decaf. His answer was, "I'm not going to say one or the other, as soon as I do another study comes out disproving the last study." He did suggest perhaps start the day with caf and midday switch to decaf. I also asked him about being on a low sodium diet, I wanted to know that since sodium was so bad for people HOW COME they had a bag of salt water piped directly into my veins!!! He tried not to smile while telling me the body needs some salt. They also started me on IV rat poison for a blood thinner, then they switched me to a different blood thinner which was shots with those teeny needles into the tummy area.

 

[JohnD]

You want stone age? This is a little closer:

Not to be difficult but wouldn't stone age more likely refer to the stoneware crocks for salt water dimmers?

 

[BillConnerFASTC]

Not to be difficult but wouldn't stone age more likely refer to the stoneware crocks for salt water dimmers?

That was why I said closer. I think handling the fire building chores at a camp fire is probably as close to stone age lighting control I can actually think of, Grunt telling story of the days hunt for the woolly mammoth or whatever. And were still telling stories.

Try one of the new blood thinners - really expensive rat poisoning. Been there done those including the heparin in the gut after being told I should not have survived the PE. I've come to the conclusion that coffee is fine, don't worry about salt - but I never add salt anyways - but do avoid sugar. All things in moderation (well - one activity I'll get all I can of.)

 

[Stevens R. Miller]

The closer to 65 I get the more I'm saying "I'm too old for this crap, where's the FNG?"

Edit ps: I see the forum software has automatic word-nanny replacements...

I ran into that too! In my humble opinion, there should be an exception for the phrase, "I'm too old for this sh_t," but I can see the host's reasoning in filtering it.

 

[microstar]

It's puzzling that it is still in the cabinet, just left unpowered. I mean, if I were the person who disconnected it, I'd have taken it out entirely for just your reasons. Perhaps the idea is that we're supposed to tell them if the problem went away and, if not, they'll just assume the PRE10A is a good one and, eventually, reconnect it.

And here is yet another example of how frustrating this all is for me: Someone made a significant change to the system, yet no one in my company has heard anything about it. None of us "lighting people" (as our director calls us) did it. No one has told any of us who did it. The assistant principal hasn't contacted me, even though I wrote him a detailed problem report yesterday morning (before, I assume, anyone came to work on it). I'm guessing the contractor showed up, told someone in the front office, "I'm here to work on the auditorium lights," and staff just let them in. Maybe an hour later, with the PRE10A disconnected, that person went back to the front office and said something like, "Okay, I made a change. Have them let me know if that fixes it, okay?" Staff probably said, "okay," and forgot that he was ever there, with the assistant principal never knowing anyone did anything.

I'll send him an e-mail and ask, but I had given him my phone number and he had said the school would call me when and if a tech came. I work at home and can be there in 20 minutes.

Art is about suffering, I guess.

I understand perfectly, it happens all the time when servicing school stuff. The left hand doesn't know what the right hand is doing most of the time! Just hopeful unplugging the PRE10A was the solution to the problem.

 

[Stevens R. Miller]

My six new Crummy Chinese Lights have arrived. Got one out and up on the bench. Early impression is actually pretty good. It's bright enough to be useful, pulls 0.46A at 56W (according to my Kill A Watt meter), and its fan is whisper-quiet. Reacts correctly to my DMX instructions. Uses eight addresses, with no option I can find to change to anything less consumptive. That's kind of disappointing since I only need four of those eight (the first four control mode, color, speed, and master dimming, where "mode" means something like "strobe," "fade," "sound activated," "DMX," etc.). The last four are Red, Green, Blue, and White, which are all I really need. Still, one could put 64 of these into one universe. That's more lights than I've ever had to work with, so I'm not complaining.

Now, having just uncrated them, I can't say anything yet about reliability, nor much about durability. On the latter, they're clearly not going to take harsh treatment well. But they're reasonably solid, with a plastic enclosure about 1.4mm thick and two metal brackets with knobbed bolts. The brackets appear actually to be slightly different sizes, so one can fit just inside the other, which is good if you need to hang the instrument from a pipe (can use both brackets for a really rigid yoke). As predicted, the dimming curve is rather logarithmic, but I can live with that. The beam is a bit more spotty than I had expected. I anticipated a wider angle.

Oh, say, here's a question for you professionals: when the lamp casts a spot with a soft edge, how do you measure the angle? Just eyeballing it, I estimate the "working" part of the spot is about 30 inches in diameter, when cast from five feet away. 15 inches over 60 inches is 0.25, the acrtangent of which is about 14 degrees, so I am thinking this casts about a 28-degree cone. Is that anything like how it's supposed to be measured?

 

[BillConnerFASTC]

Beam angle to 50% from center, field angle is to 10%.

 

[Les]

The brackets appear actually to be slightly different sizes, so one can fit just inside the other, which is good if you need to hang the instrument from a pipe (can use both brackets for a really rigid yoke).

That has been a trend with LED fixtures. It's known as a "kickstand" by some, and allows you to set the unit on the floor without needing to bolt it to a base.

 

[RonHebbard]

Art is about suffering, I guess.

@Stevens R. Miller Art is not about suffering. Art IS suffering.
Toodleoo!
Ron Hebbard.

 

[RonHebbard]

I ran into that too! In my humble opinion, there should be an exception for the phrase, "I'm too old for this sh_t," but I can see the host's reasoning in filtering it.

@Stevens R. Miller @TimMc You can probably get away with "I'm too old for this excrement!" and / or "Equine excrement" in lieu of BS. And then there're always my old standbys "Phuque!" and "Phucough!" Poor SpellCheck doesn't have a clue.
Toodleoo!
Ron Hebbard.

 

[Stevens R. Miller]

That has been a trend with LED fixtures. It's known as a "kickstand" by some, and allows you to set the unit on the floor without needing to bolt it to a base.

It works pretty well. As I uncrated the other five and assembled them, I noticed that not only does one fit well inside the other, that "insider" is also a bit wider than the "outsider." Makes it easy to tell which is which, though I can't think of any other advantage to it.

One of them does have a slightly flaky XLR3 on its output side. That may be my cable, though. If it's the lamp, I will open it up and see if I can correct the problem. The shells aren't sealed. Appear to be serviceable with an ordinary Phillips.

Here are some pix on my bench:

They do produce the saturated colors that I have noticed are characteristic of LEDs.

Kill A Watt confirms they pull about 2.8A total, at 343W, when full up.

That last pic accurately shows that they are bit on the magenta side when you would want them to be as white as possible. Will have to correct for that in the color mix.

 

[Stevens R. Miller]

@Stevens R. Miller Art is not about suffering. Art IS suffering.
Toodleoo!
Ron Hebbard.

Now he tells me...

 

[RonHebbard]

Not to be difficult but wouldn't stone age more likely refer to the stoneware crocks for salt water dimmers?

@JohnD Imagine, three scene preset, salt-water dimmers; Now imagine trimming them.
Toodeoo!
Ron Hebbard.