dvidos Posted February 29, 2008 Share Posted February 29, 2008 Hello,hoping my post is usefull, I suppose I could also give something back to the community. What follows is a simple Cue Lights system I designed. The design goals were: 1. Have the ability of daisy chaining the outstations. 2. Have the ability for the outstations to signal the master, when idle and as an acknowledgement. 3. Have the ability to control outstations per channel or per group. 4. No complex electronics, just switches, LEDs, resistors. http://lh6.google.com/dvidos/R8KyhK_HCCI/AAAAAAAABGA/7W21yhEJMj0/s144/Cue%20Lights%20Schematic.png For per-channel usage, leave A to red and B to green. For group usage, set the channels to group A or B and use the group switches. Channels 4..6 are not shown for space as are outstations 3..6. When an outstation presses its button, both lights come on. For cable, I went for cheap Cat5, having 8 wires, hence the 6 stations. For the outstations, cheap wall mounted dual ethernet ports can be used, as seen here There is a possibility I have made mistakes. Please feel free to point them out. Comments and improvement ideas are welcomed as well. I have to admit I have not built the system yet, as there are other projects in higher priority right now. But many people ask for circuits of cue lights, so I thought the schematic would be useful. Cheers,Dimitris. edit: sigh... should have built/test it first: when channels are grouped, the feedback from stations would signal the entire group. Mods: please feel free to delete this post. Link to comment Share on other sites More sharing options...
dbuckley Posted February 29, 2008 Share Posted February 29, 2008 I think it would work with the drawback you note, however, if my brain is working at 00:35am, then you want the LEDs in series with one resistor rather than paired in parallel; LEDs conduct when forward biased like any diode, but light up when reverse biased. The only other drawback is that you only see the acknowledgement if you are looking at the LEDS when the button is pressed. However, if you accept you only acknowledge the red standby, as is the normal practice, then a single relay set up to self-latch fed with a diode from the switched line would be all that is necessary to have a locked Ack light at the master end. Link to comment Share on other sites More sharing options...
dvidos Posted February 29, 2008 Author Share Posted February 29, 2008 You are right David. ... a single relay set up to self-latch fed with a diode ... I had not thought of that. But then I would need a 555 timer etc. I guess it cannot be both easy and full featured at the same time...Back to the drawing board then! Link to comment Share on other sites More sharing options...
cedd Posted February 29, 2008 Share Posted February 29, 2008 I have no circuit diagrams of my system currently presentable to the public, most are on scruffy bits of paper,but it is possible to do a system involving 2 core screened audio cable with XLR's on to each outstation and with the 3 cores, have standby flashing, acknowledge button folowed by solid standby, then go. No fancy electronics, just clever use of relay latches and changeover switches. If you put 2 LED's in parallel but facing in opposite directions, you can feed the 2 of them independently (though not at the same time) from 2 cores. You just need a split power supply (-12v, 0v and +12v in my case) and a changeover switch. If the feed to this switch goes via a simple 555 flasher triggering a relay, you can flash the LED. At the outstation, stick a capacitor on the flash LED so it charges up after a couple of flashes and here is your voltage to send back down the 3rd core to switch the acknowledge. You can do it without the cap, but the button then has to be pressed whilst the LED is on so there's a voltage there to send back. A simple relay latch then changes this over from flash to continuous and cancels the latch when the go button is pressed, which reverses the polarity and lights the other LED. Did you get all that? Easier to draw than describe, but it really does work and ony needs one 555 flasher. The rest is relays, switches, diodes and capacitors. Only drawback is your outstation operator has to wait for 2 flashes or press the acknowledge button whilst the LED is on for it to accept the button press. Link to comment Share on other sites More sharing options...
ed_ Posted March 1, 2008 Share Posted March 1, 2008 At the outstation, stick a capacitor on the flash LED so it charges up after a couple of flashes and here is your voltage to send back down the 3rd core to switch the acknowledge. It's been a while since I've done this kind of thing, and it's also three in the morning so I might be completely wrong, but is the idea that you'll maintain 1.4v when the LED is off without discharge through the LED due to the diode voltage drop? Link to comment Share on other sites More sharing options...
cedd Posted March 1, 2008 Share Posted March 1, 2008 Actually I missed out a point, the LED's I'm using are 12v LED's, so there's a full 12v going to the outstation. The cap stores this 12v up because if you think about the circuit, to acknowledge the standby, you have to send 12v back down a leg of the cable to the master station. To do this you obviously need to hve a source of 12v at the outstation. I take this 12v from the standby LED which is fed 12v from the master station. However...... as the pre-acknowledged state of the standby LED is flashing, this 12v is only there half of the time. The cap makes sure it's there all of the time. A big enough cap and a diode will make sure you have 12v present permentantly after a couple of flashes. I am trying to get this thing drawn up, but as I haven't finished the unit yet, it could take a while. I do however have one working channel so I know the system works! Link to comment Share on other sites More sharing options...
henny Posted March 1, 2008 Share Posted March 1, 2008 how about stanby being on and flash for acknowledge this would give you constant power for the reply Link to comment Share on other sites More sharing options...
Johnno Posted March 1, 2008 Share Posted March 1, 2008 (snip) LEDs conduct when forward biased like any diode, but light up when reverse biased. LEDs light up when forward biassed and don't pass any current when reverse biassed, like any diode. Link to comment Share on other sites More sharing options...
dbuckley Posted March 1, 2008 Share Posted March 1, 2008 See thats what happens after midnight; I get LEDs and Zeners confuzzled :D Link to comment Share on other sites More sharing options...
dvidos Posted March 2, 2008 Author Share Posted March 2, 2008 I have no circuit diagrams of my system currently presentable to the public, most are on scruffy bits of paper, (snip) You just need a split power supply (-12v, 0v and +12v in my case)I really would like to see a sample diagram on the connections (PSU, switch, relay, 555) of your solution Chris. It does not have to be quality... To make things simpler for me, I am sending power and ground over the chain. Every station will have an additional pair of cables, one for the LEDs, one for the switch. But I want it to be able to signal the master, even when not on standby. I am lost somewhere between using AC, or using +12/0/-12. Mods: should/could I create a page in the Wiki for Cue Lights, along with some schematics? Moderation: "The wiki is not a spectator sport" so do what you want :o, but more seriously go for it, sounds like a great idea Link to comment Share on other sites More sharing options...
cedd Posted March 3, 2008 Share Posted March 3, 2008 how about stanby being on and flash for acknowledge this would give you constant power for the reply Indeed that would make life easier. I still think a cap may be required as in effect as you press the button it would immediately disconnect the supply. You could end up with a jittery relay. Never tried it so I'm not 100% sure, it's just what I suspect will happen. Is there a reconised flash/colour code for que lights? The ones I've seen have been flashing red until acknowledged, then red solid once acknowledged and green solid for go. That's what I was trying to mirror for my system. An ideal system would also have an intensity control so more visible stations in the wings aren't going to flood the area with light, whilst ones in the fly's can be brighter. Once I've got the outfield hardwear done and the control hardware sorted, I will start playing with the control side of things. At the minute each channel has a 3 position switch, centre being off, up is latching and is standby, down is momentary and is go (hold down until you see the cue has been carried out) which may well get fiddly if you get lots of cue's at once as the limiting factor is number of fingers free to hold down buttons. I've never seen a system that acknowledges a "go" but I suppose it could potentially be done to say a cue has been carried out. Link to comment Share on other sites More sharing options...
dvidos Posted April 1, 2008 Author Share Posted April 1, 2008 Would anyone care to take a look and comment on this design? I think it will work, but I would also appreciate a second opinion. http://lh5.google.com/dvidos/R_JAmszsNdI/AAAAAAAABIQ/tMe0VoA44Ro/s400/Cue%20Lights,%20rev%20C.png Features: Flashing red, acknowledgement button turns it solid, green for GO. Plus, an amber LED for the station to signal the master, even when not in standby. Just one relay and one switch per channel. No daisy-chaining and no grouping for at the moment. edit: bad expression. Link to comment Share on other sites More sharing options...
themadhippy Posted April 1, 2008 Share Posted April 1, 2008 why bother with the 555 and its associated circuitry,cant you use a flashing led instead,+ve to one side of the flashing led the other side into the blink relay Link to comment Share on other sites More sharing options...
david.elsbury Posted April 2, 2008 Share Posted April 2, 2008 Yes, but you can't turn a flashing LED into a solid one to signify an acknowledge, down the same 3 core cable, which is kinda the point, Mr Hippy... Link to comment Share on other sites More sharing options...
themadhippy Posted April 2, 2008 Share Posted April 2, 2008 but you can't turn a flashing LED into a solid one to signify an acknowledgethe solids leds are still in the outstation,the flashing led replaces the 555 pulse genarating circuit. Link to comment Share on other sites More sharing options...
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