TomHoward

Yes, that display board got a fair bit more progress on it on Saturday due to the big steeldeck build we were supposed to be doing got pulled... not before we’d unloaded it but at least before we’d built it.

Latest development is a full set of 9 letters just at 2 pixels per segment for programming / testing. A lot of fiddling wiring in that.

Thanks, current draw is a concern so WS2815 may not be the ticket. We’ll probably make the first with 2811 and see how it goes at first. Printed a full sized number but not wired it yet

Just reliability, in case of any stray bits inside etc, but it is a bit of a bugger as it may be harder to tin both ends. Originally when I was thinking of pouring resin in I was planning bare wire for ease because it would be cast in place.

Thanks, hopefully it'll be fairly sealed inside as it'll be like the one above with a lid on. For the proper ones I'm thinking of either using transformer winding wire between then instead of bar (so it has some insulation) or printing divisions for the wires to keep them isolated as well. I might run the 12V into the middle of the tapes separately away from the data if it's a bit tight.

It's a thought, the WS2815 is interesting, I'd seen the WS2813 but I didn't want to go 5V I'd rather go 12V as the current just goes through the roof at 5V and the batteries and power supplies aren't as easy either. With the WS2815 tape, if there is a dead pixel, does the next pixel behave one address sooner (ie it all shifts one pixel to the right) or is the dead pixel bypassed but the address accounted for? As if it all shifts one pixel on, it doesn't really work for 7 segment as it'll be lighting up one of the next segment and need repair / replacement much sooner anyway. Edit: It seems this rather basic question has been answered previously and it should drop the data from the missing pin when using the backup pin: https://www.blue-room.org.uk/index.php?showtopic=73153

To be honest, if I can make every digit modular and exchangeable, that'll halfway do as they are relatively low cost per digit. I'm planning to cut tops and glue/silicone them on to make them semi-removable rather than pouring resin over them any more so they may be able to be cracked open to exchange lengths of tape. It is true about the entire scoreboard running downstream of one pixel so I will explore running it in multiple circuits so hopefully only one line or one figure may be driven from one output if it's viable, so have several universes of output for each board to separate the data, so hopefully we might only lose one digit or one line. We were thinking of driving static LED tape instead from shift registers but the amount of wiring and work really increased. I'm hoping to keep it really serviceable and then make a stock of spare digits that can be swapped out, as we are printing & cutting them on site hopefully we can keep them running.

Our one we disabled the IR switching as it was getting stuck in it and didn't aways recover for a dark scene. It's mainly used for cast relay monitors backstage rather than SM / operating so not seeing in the blackouts was less of an issue than it getting stuck whited out. It was pretty easy to disable the IR switching once it was opened up, did it by removing a key component but unhelpfully I can't remember which one.

That’s what I’m going to try - I’ll still make a full sized one as prototype but make a single strip one as well and see whether one strip at 100% or two strips at 50% are more readable at around 200m. I don’t know whether a colour might be more readable than white in daylight as well - eg red might actually be more visible than white maybe due to the contrast? The only thing I’ve done since is print a cover with just the LEDs showing, which works well as a concept but is a bit of a shabby print as I tried just two layers thick and didn’t have the height set too well. Might try getting these laser cut instead which should be faster & neater.

So far I've made a 3rd sized mockup. The thing uses WS212b so has 21x pixels and draws about 5.25W or just over 1A at 5V. The plan is to use WS2811 so it can be run at 12V and double up the strips as in the picture above, so the final one would have 126 LEDs, pull 35W so be 2.6A at 12V. This is a bit of a problem as with nine in a display it could pull 23A max and actually need some fairy serious batteries if it were to be mobile. We might have to scale the size down a bit for the mobile version if it's to be battery powered. 1/3rd sized character: Wide shot on a messy desk, because it's hard to judge from the video just how bright it is: YouTube link:

Ah, they look pretty much like what might be on the current signs already, or something already made up to 7-segment. I was thinking two lines of 5050 60/m next to each other, something like this mockup in old school single (but to give the idea: Cutting a laser / printed top to cover the strips apart from the holes might be a good idea. I was going to use black strip on a black backing already but I guess cover the white elements even more might work well in terms of visibility. Going to make some test ones - currently making a couple of small ones for programming then I'll make some large ones for testing the visibility.

You won’t need 12 channels of control, 3 should do. Those LEDs claim 24V so they should be okay to use. They’ll be wired in about 8s, and each 8 lights or so the twisted wires will go from being 3 wires twisted together down to 2 wires, which is the feed into the next section. You could cut it there or just order two strings and twist them together. If you’re running two whole strings, it will probably draw more current than the supplied power supply could give, as you’d be combining them into one string at the controller, so you may need a higher current 24V power supply. 3ch controller: https://www.amazon.co.uk/Candybarbar-Professional-DC12-24V-Decoder-Controller/dp/B07WBYMVX7/ref=mp_s_a_1_7?keywords=3ch+led+DMX&qid=1583789115&sr=8-7

I concerned about even being able to read an LED when it’s fully on, but we’ll see. I think it’s refracting within the LED, the 3rd image with what looks like lens flare and refracted colours, it actually looks like that in the flesh, if you turn the part 90degrees to the desk you get a few hard lines of individual colour coming out, something’s going wrong in the beam angle for sure.

I'm not a fan of the silicone covered tape either, as I find the sticky glue on the back can't take the weight so prefer the uncovered stuff, but also I've found it burns the back of the silicone where it touches the chip over time and what looks like the LED output reducing is actually just burnt silicone blocking the output. If you pull the silicone off some tape with high hours you can clearly see the black and tape looks a lot brighter. Here's my rather shabby test rig - built up with hot glue and then poured in. With the uncovered tape, when poured on, the output is reduced, or at least the focus is knackered: (With this image, the tape is running at about 5% level for the photograph, at 100% the image doesn't photograph well but it is still visible to the eye) I didn't have any silicone covered WS281x tape to test, so I had to use RGB silicone tape. However I didn't have a dimmer for this set up, which means I just ran 12V into it so it's at 100%. The effect is pretty much as bad when poured in resin as the uncovered tape, which I wasn't expecting, I thought the silicone tape wouldn't be effected as badly. You can see 'haloing' around the LED, which you can see by eye as well. If you view it from a shallow angle there are sudden 'bright spots' when you're looking from the side, so I think it's the beam angle being totally knackered and the output prismed into it's component colours. So, given the trouble with pouring resin over, we are likely to look at laser cutting 2mm Acrylic sheet or similar for the top, and then print a lip for that to sit into and seal it with a small bead of silicone / glue etc. Given the segments are going to be used in full sunlight, and are supposed to be visible from 100m+ away, I'd rather keep the contract as high as possible, so I'd rather use black tape on a black background facing straight out than rely on any reflection off a white surface, or add white diffusion or similar over the top and rely on the illumination through it - as I imagine the sunlight reflecting off the diffusion from the front will also light it up and reduce the contrast. I don't know whether using a colour for the pixels as opposed to white might increase visibility also.

We were using this kind of LED PWM dimmer, cutting off the LED's power supply and dimming it on the string after the power supply- As said a lot of them use LEDs wired in both directions to give two circuits and pulse between them, so driving them is a bit of a nightmare. It would probably be easier to find 3 static strings that run in the 12-24V range and twist the three together

I'll post some pictures later, but I've just done a very rough test rig, the resin hasn't gone off yet but lenses or no pouring resin over the bare silicone-less 5050 tape definitely affects the output of the LEDs and they are like little RGB spots rather than a mixed colour. I might try with some of the silicone covered tape, I prefer the bare stuff myself but I don't know whether pouring over the stuff that is already silicone covered might fare better.

Could you find a 3-circuit chasing warm white string, cut the end off and run it off one of those 3ch DMX led drivers meant for RGB tape - tend to run a reasonable voltage range. I’ve just made a set running at 18V off a Makita battery for a truck with wireless dimming but used artnet receiver into DMX and just used one of those dinners rather than going WS281x, it’s only one static circuit though not multiple For ease of identifying circuits etc you could just wrap three static sets together. Beware of the two-circuit chasing lamps as they often run off one string with have the diodes inverse, you could probably drive it as two circuits again with some rectifying but it would take more thinking about. https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.co.uk%2Fulk%2Fitm%2F112978858890

Thanks for the pointers. I was going to use through hole as I thought it would be neater than strip, but thinking about how many of these I've got to make I'm going to go with the minimum work per unit and try addressable WS281x tape stuck into 3D printed housings, then just power & data for each unit rather than having to do 8 wires. As these are going to be outside for a long time, I don't know if the print material will matter - I don't want to be remaking them in a year if they've fallen apart..

Thanks for the pointers, I am thinking currently of using LED tape as suggested, but rather than printing segments and enclosing it I am thinking of using it bare on the surface and maybe pouring resin over it to encapsulate it. At the moment I am having the same thoughts about 'analogue' LED tape vs WS2812 tape. With 7 segment tape, the first 9-digit display would be 63 segments, so that's a lot of cabling with traditional tape and 8 cores to each figure. WS2812 / WS2811 tape might be much easier as only 3 core wiring all around the piece and it can daisy chain, but needs some more software but much lower component count as well as shouldn't need the transistors etc for switching. This example uses bare tape, and the commercial units we have at the moment are bare thorugh-hole as well, which I'm also considering but more work

Evening all I am hoping for some ideas for oversized 7-segment display. At work we are looking at building an in-house cricket scoreboard, that takes data from a widely used app over bluetooth and displays data. The bluetooth / app / programming side looks all sorted but I'm wondering about how to make the giant 7-segment displays needed. I'm hoping to make them as units so I can swap them out / wire as needed so they can be swapped and repaired on the bench rather than on the scoreboard. If this project takes of we may make ones of different sizes so something modular would be good. The ideas I have at the moment are: Use LED strip and transistor drivers to make the shapes Use WS2812 tape and custom controller and drive them 10px at a time or so to make 7 segments. Laser / CNC cut a load of holes in a piece of thin material and push through-hole LEDs through and wire them up bending the legs over. Then to waterproof them: Fit a perspex top Make a back plate with a ridge and pour clear resin over the top to cover the tape / LEDs and set it in resin somehow avoiding air bubbles The aimed size is about 30cm high x 15cm width. I'm imagining with LED strip in either type it would be multiple strips to an edge. Thanks for ideas!

Thanks for all the above. We are currently looking at Panasonic 10 / 12ks as above from AC-ET. Looking at the screens, is there a big difference in screen quality? I'm also trying to work out cost between a double-drop / twin motor screen and installing a winch motor to lower a bar with a single stage screen on it. Currently the screen takes up one of our motor winch bars, but there are about 10 fixed bars it could go on instead with an additional winch installed.

Are the ultra short throw projectors usually used on classroom whiteboards of any use? They usually seem to have a greater than 100% offset as they are mounted above the board. They are not usually 5000lm usually more around the 3000-3500 mark but something like the Optoma ZH500UST advertises 5000lm. Usually they are run lens downward mounted above the board so you'd have to check the operations for for which can be used in either orientation.

I bought an UAP-AC-M and a ER-X. The erx has a wizard to set it up just as a switch, then add the DHCP back in. It’s really easy to assign static IPs at the router level so I should be able to set statics for our desks in the router, then leave the desk on dhcp but still have it always on the same ip for the app. The UniFi APs, I tried running the controller on my computer but gave up as I couldn’t get it to connect to the ap. I used the iPhone app and you can run the ap in “standalone mode” via the iPhone app where you scan the QR code on the back of the AP in the app, configure your SSIDs and all your settings then deploy them one-off without having to “adopt” it on a controller. (I think the controller software was a bit problematic because I’m doing it on a network managed desktop without local admin, etc, probably easier on a home computer / laptop)

I don't think we are likely to want to change the setup too much, the setup currently is: X32 or rack with static IP about 4 wired/wireless Artnet nodes with static IPs one iPad with Lumair for Artnet generation likely on DHCP one or two iPads for X32 control, likely on DHCP. I'm most likely looking at a UAP-AC-M and a ER-X router. Once the setup is done, the reconfiguration of static IPs is mostly on the nodes rather than anything intelligent really being done in the router. Only thing is with the multiple artnet nodes on Luminair we have to run the Artnet on Broadcast, rather than unicast, I'm hoping this extra traffic won't give the X32 any trouble. Main priority is the range & reliability of the Artnet nodes.

I have to correct my comments above, as we are now using multiple SmartShow nodes and have no problems with them at all. We have a mixture of NetDMX and airDMXout and they both work great with Luminair or QLab. Using broadcast mode on the network you can use multiple nodes with either of these software - we're switching to Luminair for smaller events and trying out using wired products on the dimmers and wireless nodes up in the air which should really cut down running cable around the rooms. The nodes are really keenly priced as well - currently under £50 for the airDMXout wireless artnet-DMX node.