pdowns Posted November 9, 2009 Posted November 9, 2009 I'm adding some strobe lights this year and noticed that a few of them will continue to fire once, even twice after the power is removed from the string. I know why, energy stored in the capacitor ...This isn't a BIG DEAL but I'd prefer they quit flashing when I want rather than some time later. Is there a simple solution anyone can suggest?
iresq Posted November 9, 2009 Posted November 9, 2009 Simple solution, replace with LED strobes. You could try to move the off command up a bit.
George Simmons Posted November 9, 2009 Posted November 9, 2009 Yes, the LED strobes quit firing completely when the channel shuts off. The only problem with LED strobes however (at least with the ones I got from CDI) is that they fire in complete synchronization for up to ten seconds. Turn them off for even half a second and then back on and they'll fire in synchronization for the first ten seconds or so again. If that's what you want, I'll sell you a bunch of the ones I got since I won't be using very many of them this year.
pdowns Posted November 9, 2009 Author Posted November 9, 2009 That sounds like a major shortcoming with the LED strobes. I'd rather live with a few extra flashes. As I think about it, it seems like it's always the same bulbs that do the extra flashing. Maybe their capacitors are slightly larger. Perhaps I should consider replacing a couple bulbs.Did I buy extras? No! Guess I'd better ...
Greg Posted November 9, 2009 Posted November 9, 2009 I did what dave had said and moved the off command a bit. that should solve your problem a bit
friskybri Posted November 9, 2009 Posted November 9, 2009 You would figure CDI would have tested a string of them before selling the LED junk. Not happy with the 50 LED stuff I got. I might be making a rush order for 30 Regular strobes and mix them in if it really sucks. Will try the week prior to see what it looks like.
George Simmons Posted November 9, 2009 Posted November 9, 2009 I, too, have/will be mixing both types of strobes together to try to dilute the synchronized effect of the LED ones. But still I won't be able to use all the LEDs I wasted my money buying from CDI this year. Bummer... I'm also going to use up to eight channels (across two city lots) for strobes and offset the start times slightly in my sequences to try to reduce the synchronized effect of the LED's. Unfortunately, I don't have enough extra channels to really do it right.
Richard Hamilton Posted November 9, 2009 Posted November 9, 2009 pdowns wrote: I'm adding some strobe lights this year and noticed that a few of them will continue to fire once, even twice after the power is removed from the string. I know why, energy stored in the capacitor ...This isn't a BIG DEAL but I'd prefer they quit flashing when I want rather than some time later. Is there a simple solution anyone can suggest?Like others suggested, turn them off earlier. I turn them off about 250 milliseconds before the actual time I want the last strobe to fire.Also you may have noticed the opposite effect. When you turn them on, they don't fire right away. I solve this by "precharging". A few seconds before I want them to come on, I send a 250 millisecond on/off sequence to the strobes. This charges them without causing a flash. Then when you hit them with the actual "on" command, they fire instantly so the audience won't see the delay. Optionally, just turn them on about 200 msec early.Obviously strobes are not manufactured exactly the same way and the capacitors in them aren't precise, so it's not an exact timing, but close enough.
JeffF Posted November 10, 2009 Posted November 10, 2009 George Simmons wrote: I, too, have/will be mixing both types of strobes together to try to dilute the synchronized effect of the LED ones. But still I won't be able to use all the LEDs I wasted my money buying from CDI this year. Bummer... I'm also going to use up to eight channels (across two city lots) for strobes and offset the start times slightly in my sequences to try to reduce the synchronized effect of the LED's. Unfortunately, I don't have enough extra channels to really do it right.Yep, I'm stuck with 30 LED strobes also. I'm mixing them in with the 80 or so regular strobes I have but like you guys... I'm not happy. This is something that really should have been tested/disclosed by CDI *before* sending any units out. I do have one idea in the back of my mind I'd like to try but it involves using a load of SPT-1 to spread all the LED strobes out on the front of the house. It might look neat having one channel of strobes that respond alike.
pdowns Posted November 10, 2009 Author Posted November 10, 2009 Thanks to all for the responses. It's amazing the small tweaks that need to be applied. Richard, I hadn't even thought about the delay to the first firing. I haven't had the whole display turned on with music yet but of course I want the strobes to initially fire on tempo.I'm definitely going to use your "precharging" technique.
LENNY RUEL Posted November 10, 2009 Posted November 10, 2009 Didn't a few weeks back one of the guys found that if you turn on the LED strobes .65 early at 20% intensity it precharges them as well as makes them fire randomly?Lenny
friskybri Posted November 10, 2009 Posted November 10, 2009 It does help to do that but the strobe does come on with a dim steady light at 20%. With no other light near it will show up. However next to other lights that are on you cant see them. I was the one that was working on that. I am going to try that but if you can see them to much I will order about 30 regular strobes.
LENNY RUEL Posted November 10, 2009 Posted November 10, 2009 I actually programmed that in to all of my sequences. Not much I can do this year, and I bought regular strobes for the inside of the mega tree since I can't have those all pointing at the street like I can the ones on the house. I'm going to trust with the street light across the street that the low glow won't be noticeable and .65 goes pretty fast.Lenny
friskybri Posted November 23, 2009 Posted November 23, 2009 OK got all my stuff up and is running well. I only noticed a few times that you can see all of them come on for .65 seconds. Most of the time everything else was lit up and didn't notice the strobes. It did look ok. for the mega tree next year I will buy xeon curtain strobes. I ran one long string all over the display
LENNY RUEL Posted November 24, 2009 Posted November 24, 2009 Brian:I actually got mine all set last night on the roof and plugged the string in when my feet where on the ground. I'll say this.... They look much better than I expected.Mind you I made a "tower" for each one so they point at the street. To accomplish this I took paver bricks and mounted a 1/2" x 3" angle bracket to them with a couple Tapcon screws. I prebent the bracket to match the slope of my roof line. Then I took 1/2" sch 40 PVC and cut 2 ft and 3 ft lengths and pushed them down over the brackets. This is a snug fit and you actually need some easy hits with a hammer to do it. On top of these then I glued "T's" pointing to the street. I used a dremmel with a cutting disc and cut a 1/4" wide slot out of the top for the cord to fit coming out of the C9 sockets. I made up my light cords then by adding 6' to whatever the height was and putting the socket on one end and a plug on the other. Slid the socket and strobe in to the front of the T with the wire pulled towards the back, ladder tied the cord down the tower and plugged them in to my main feed line.Plugged them in and they looked good by themselves. The test will be when both they and the Xenons in my mega tree go off together. But they are bright, even when viewed from a better than 45 degree angle from directly in front on the house.And the fire is a lot more random than I expected off the reviews I've seen. There may be some pairs that go at the same time, but with numbers that would be expected. Of course the other big test will be when we light up and they are coming on by command when asked to.Lenny
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