Man, a cup of coffee and some Big Clive makes my morning PROPER! I'm not an electrician by trade but more by hobby and happenstance. It's so awesome learning from someone of your skill and knowledge level.
I knew it! I found your videos by accident and have spent a week solid watching pretty much all of them. I work in the home automation industry so do electronics every day but have a back ground in live production. I did sense that you had something to do with this background and I was right lol. Good work.
God said: "Let there be light!" And behold, there _was_ light. Because Clive had already been there and stretched all the wiring and installed all the light-fixtures. So it was just to flick the switch. You who work with lighting have probablly neeewer heard that one before : )
Cameron Marks The unfortunate part is that the industrial gear costs considerably more than a pound. So buying stuff just to take to bits would get expensive very quickly.
+bigclivedotcom Good point, but if you scour the used sections of eBay, then you can find some interesting and cheap things. Maybe you should open a PO box, but I don't know how well that'd do considering that you live in the isle of man :/
I'm an amateur radio operator, and wow, have I had my share of issues related to standing waves. Most issues for us hams are about the antenna itself, though, rather than the transmission line, and it's all about the resonant frequency of the antenna. Usually we use 50 ohm coax, and then we use an antenna tuner, basically an LC match circuit, to match the impedance of the antenna to that of the feedline at the desired frequency. Most transceivers are quite tolerant, but simple homebrews could blow the final transistors when transmitting into an improperly matched antenna system.
Hey Clive awesome video! I work in the entertainment industry doing lighting and i see people using cheap 3 pin XLRs for dmx all the time and then they spend soo much time trouble shooting DMX errors.
EddyGurge 10Base-2 aka cheapernet doez use looping and termination. But it's single-ended signaling over 50ohm coax, while RS485 is differential over shielded twisted pair.
The more expensive ones tend to have a micro in there that will rebuild the DMX signal, so that you have a "fresh" output signal on all the outputs. Passive splitters like this will not repair any signal degradation that occurs along the way. Active splitters will. In some cases, this can be useful. For instance in very long cable runs.
jaaasgoed I prefer to buffer it up well before it's been degraded that far. I'm slightly notorious for being lavish with buffers. The slight downside of the active units, especially the bidirectional RDM type is that if the processor crashes you either lose your data stream, or worse it can jam the whole universe it is on.
If one of the mains transformers had been rotated 90 degrees it would've reduced any coupling between 'em ... Not a problem, just icing on the cake :-)
The part which you said that a 100 ohm or 120 ohm resistor being used as a terminator is used quite widely in data transmission. One example would be the connections from a PC to a monitor where you would have a power amplifier and a non inverting amplifier for the same data (the reversed polarities of signals would help in the interference issues and restoration of the signal, on the other end it is capped off as well with a resistor to prevent mirroring of the signal :) I think that it is a connection from a pc to a monitor.. VGA type things.. I may be mistaking it with sound connections..
The most infamous "termination" horror stories in IT pretty much come from one of two things: 10Base2 Ethernet (or (shock-horror) 10Base5, for the *really* old fogies), or scsi. With coax Ethernet, you need termination on both ends, or things will go horribly and unpredictably wrong. With SCSI, *most* of the time you only need it on one end of the cable explicitly, because most SCSI cards included a terminator pack on board and mostly it was active by default... But note the qualifiers, if you forget to check it will be the one time things go bad - and then the consequences are data loss on your hard drive cable.
I was just a kid at the time, but I remember my friends dad 15 years ago or so talking about SCSI drives. I don't remember much about them specifically, but I remember that at the time they were quite a contender in terms of speed. Do they even exist anymore for the average joe on the consumer market?
Loren Husky Modern SCSI uses a serial protocol (SAS) that is so similar to SATA you can often plug SATA drives in. The SCSI speed for the past 20 or so years came mostly from hard drive factories only shipping their fast drives (10000rpm up) with SCSI connections, while insisting that SATA/ATA/IDE drives would only be available up to 7200rpm . Entirely artificial. Another benefit of SCSI was having up to 7 or 15 drives per cable with parallel versions, compared to two for ATA/IDE. The biggest bane of SCSI is that the cable making industry infested the standards process, resulting in too many different connectors being standard, unlike ATA/IDE which stayed with one connector in different qualities, all compatible. Even these days, serial SCSI (SAS) has multiple connectors with similar names, resulting in otherwise good webshops getting listings wrong and selling you a useless cable. But SAS top cable speeds exceed SATA cable speeds, making it the only option for some things.
In the same metal case, they now sell four different versions (with not that much price difference): this one, an 8 port version that has only 3 pin outputs (I guess that's where their disco roots are showing), and an RDM version of both which should mean they're bidirectional.
Hi, I have a problem on two of my DMX led-par. They don't respond on any command from my DMX-controller. They work correct when I use them with there own sound-program and Auto-program. But not on any DMX-channel. I have looked at your videos and are impressed about you knowledge!
The CANBUS protocol is quite similar to rs485 and a the voltage levels are very similar and I did build a interpreter on breadboard and I got it to work with one caveat: some data corruption occurred over long runs without a buffer similar to dmx I also prototyped one of those and the circuitry of this product is very similar 🤔
@@bigclivedotcom yes it was one of those projects: just because you can do something does not mean that you should but my attitude is fuck it let's do it anyway
Could the MZ thing be some sort of zener ? We had a large network where i worked for building access control, kept getting damaged by lightning impulses, so on my suggestion the company that supplied the equipment added 2 reversed zeners, and 2 fuses to each box (crowbar circuit), so maybe that's a double zener type device ?
***** A common way of protecting the transceivers inputs and outputs is the use of a PTC fuse and tranzorb (I think the diode things are tranzorbs). The PTC fuse would protect mainly against accidental application of DC from something like a miswired scroller cable.
bigclivedotcom Often TVS (transient voltage suppressor) diodes are used. They can withstand huge currents for short amounts of time. Tranzorb is just another name for it.
I was wondering why the connectors have four wires (five for the input section), but then you mentioned the LED's haha. You also mentioned it runs over twisted pair cable, is the screen a requirement or is it optional?
PuchMaxi1988 The screen is a requirement for open cable runs. The standard does allow for the use of CAT5 cable with one pair for data and another pair as the ground reference, but it requires a screened CAT5 unless it's run in its own conduit. There are specific cables suited to DMX cabling that have a specific "characteristic impedance" of around 100 to 120 ohm. I don't particularly recommend researching characteristic impedance unless you want a headache. It's all to do with propagation of an electrical wave down a cable and how capacitance and inductance affects it.
TornTech The earth was firmly connected to the chassis with an area of the metal buffed clean for a good connection, and the lug held on with a serrated washer and locknut.
Just on cost I found most decent buffer isolators are priced higher than many low cost consoles. Fount to do a long run from a console to a lighting rig, it is actually cheaper and better isolation can be obtained by using Artnet, E1.31, on Ethernet and have full transformer isolation on BOTH ends of each Ethernet cable by using off the shelf inexpensive networking switches and routers, plus you get multi universe distribution for less cost than a good quality DMX splitter. Seeing the splitters run from $600-$1500 each does not make economic sence when better isolation can be had with a $50 4 port Ethernet switch and several $120 6 Universe Artnet to DMX converters. The Ethernet standard has high quality transformer isolation on each port, data regeneration, handshaking,, retransmissiion, etc, that DMX alone does not have. Due to cost, higher multi-universe capability, and better isolation, I've moved to Artnet DMX over Ethernet instead of much higher cost DMX cable and Isolator splitters. Many quality consoles support Artnet out of the box, such as the Leviton Piccolo series. Artnet and DMX outputs can be used at the same time.
We use RS485 at work, and we exclusively use little PC-Boards that passively split the signal into 4. Theres no reason I can think of why it should be different for DMX?
DMX has a bit rate of 250kbit/s (250kHz) and is used over long distances. It can't be split without proper buffering as signal reflections will potentially corrupt data. RS485 is just a signal standard, your system may be low speed.
Hola, realmente is a good video, felicidades. Puedes hacer un video de como se puede medir una señal dmx en un osciloscopio? Y que cambio produce el uso de una terminal DMX en la señal? Muchas gracias, saludos.
Hi, im curious, do that Showtech DB1-4 spliter/booster have integrated 120omh termination rezistor on DMX input side. And do DMX input side ground(XLR 1th leg) is connected to PE(chasis ground or from power in cable)? Thanks.
Probably not the first to tell you but those electronics gets beat up a lot on the road. These cheap but handy solutions ends up without protection between heavy gear so that is probably why they do not use sockets for the chips. It would be "broken" after 3 shows...
Is this an alternative to fiber optic lighting control systems for large venues?also at what point should I worry about using xlr cords for my dmx setups?
+AlbanyHauntCA Fibe optic is used for large amounts of channels over large areas. The point you should worry about your standard audio leads (if that's what you're talking about) is when your network length reaches a point where the lights start doing random stuff, or in the case of a professional event it's got to be proper data cable from the start.
+bigclivedotcom thanks! thats good to know. Also what kind of system would you use to run DMX in a dark ride or walkthrough atraction. I want to be able to to triger multiple scenes at the same time and also have those scenes trigger audio. Please tell me if that makes any sense. love your videos!
+AlbanyHauntCA You can get the audio repeater modules on ebay. I'm not sure the best option for triggering multiple items. It's going well and truly into the area of show control. Gilderfluke stuff comes to mind.
Can we get a schematic of the transformers and how they're configured to be completely isolated? Also can you post the schematic for the power supply side: PTC thermistors, capacitors, ferrites, full wave rectifier diodes, and voltage regulators? Thanks so much
DINKIN It's obviously bog standard textbook. 240V to few volt AC transformer. Bridge rectifier. Capacitor. RF bead and second capacitor. 7805. Add in PTCs, TVS , fuse etc. as needed. Make a complete second one like the first and stick em on the same board with an isolation gap between them, crossed only by the optocoupler.
The original standard allowed for two networks on one connector, and it also avoids issues with the DMX being mixed up with audio cables which are XLR3.
drutfurgeson definitely not what happened at the great white fire. DMX is not super popular as a pyrotechnic firing control system. even when it is used, it is never the primary firing system. electronically fired pyro systems have a manual operator switch which must be set to arm. that's regardless of the fact that the building was not suitable for pyrotechnic displays. there never should have been any to begin with, even if there was the off chance someone had 20 years ahead of time pyro systems hooked up to DMX there, they should not have hooked it up in the first place. its not a funny joke either. a lot of people died horribly
If you're lighting a show with revenue in the thousands of dollars and up, sure. If you're a mobile DJ or a small nightclub or a state fair -- and you can get away with using 3-pin mic cable because you have 50 feet total cable and all of ten lights... Seriously, NObody uses all five pins anyway. There's "proper", there's "good enough", and then "not good enough". If nobody is losing lives or (significant) money, it's perfectly acceptable to determine the difference by trial and error. The electronics do not care, and are not impressed by "proper". They live in a world of "good enough" or "not good enough".
Most of my lighting experience is with a home-made (not originally mine) 8-channel deathtrap box with standard household dimmers and NEMA-15 outlets, running on mains 110v AC with a power cord per channel running from the board at the back of the gymnasium to the stage at the front (lots of gaffer tape is used). I've only used a DMX control system on a couple of occasions where the school's production budget was high enough to facilitate renting a proper lighting set (despite my attempts to persuade them to get our own set). They were all DMX-3. Have you ever encountered a DMX-5 system that actually utilized the second data pair?
I have encountered plenty of systems to incorporate those pairs due to the fact it is part of the standard, however, I haven't opened them up to see if they actually use it or not. If you're setting up a small lighting system, you'd probably be best of using a USB to DMX 3Pin, like this www.ebay.com/itm/New-USB-to-DMX-Interface-Adapter-DMX512-Computer-PC-Satge-Lighting-Controller-US-/281730984904?hash=item419879abc8:g:ODgAAOSwT6pVihQK Using freeware with a laptop/desktop which I'm sure the school can provide, and those splitters are much less expensive. Like this www.ebay.com/itm/LED-Controller-DMX-8-Channel-Output-DMX512-Signal-Amplifier-Splitter-Distributor-/222254953371?hash=item33bf6d739b:g:1tAAAOSwmfhX39GV As far as cheap lights within their budget LED's are the cheapest option right now, and for a basic small stage, you can light it quite effectively using a set of these for instance: www.ebay.com/itm/10x-86-RGB-LED-Stage-Light-Par-DMX-512-Lighting-Laser-Projector-Party-DJ-Disco-/301672148579?hash=item463d0fae63:g:oNQAAOSwU0RXHYvs And the wonderful thing about those is they require NO DIMMERS, Simply power, and minimal power at that. So running the power is as simple as wiring up some standard NEMA power to a grid. With no dimming at all. I'm no electrician, but that isn't hard. Focusing is dead easy too, just point. And after initial setup little setup would be needed as long as you set up each LED on it's own channel range and have a good way to deal with that, maybe upstage, downstage, centerstage, left, right ETC. And that's how you make a dead cheap system. Would it work? Probably. Would you make a lot of admins and parents happy? Definitely, if it worked. And I see no reason why it wouldn't. And if it's not a professional stage, I think you'd not get any complaints. You could easily set this all up for much less than a grand, if you had a grid already. and even if you didn't just a way to mount them should suffice. Cabling and stuff would be the majority of your cost.
I didn't know they made USB-DMX controllers. That's quite handy. As for the generic LED cans, they look easy enough to use, but given the price and lack of any kind of lens (or other spec data such as lumen output, beam spread and focal length), I'd say they're more for effect (disco/DJ stuff) and would be pitiful for stage lighting. My setup typically uses 12-18 tungsten filament flood lamps with typical wattage of 100-150w each. I also need something with a somewhat focused beam, of the kind a PAR can can provide so I can do discrete lighting zones. They'd be good for the school dance, certainly, but not stage lighting. And anyways, I'm not doing the school's productions any more, I'm afraid. As much as I loved doing them, I just don't have the time any more.
Perhaps not stage lighting yes I agree, but you'd be surprised, for the cost its quite good! And for a small black box production that requires just lighting the stage, one could probably get away with it. With a bit of tinkering of course ;) But yes time is the ultimate factor. I have hardly any time to spend on non profit low budget stuff anymore unless its for my own home! Haha
how hard is it to make DMX devices, I can't seem to find simple low voltage DMX relays that don't cost obscene amounts like those from Doug Fleenor Design which is a shame because I would love to be able to solder in all sorts of cheap eBay lights to toggle on a console.
If you have used Arduino, it's very simple. There are a few library's out there that'll do what you want. Connect a max485 into the arduino serial input and write some code. I've made a double relay unit and also a 5xRGB led tape controller. Both have been very reliable over the last 2 years with approx 7-10 shows per week. The only issues they've had are all due to inadequate short circuit protection on the outputs - a conscious decision to save costs and space but I wish I'd used auto resetting fuses. I used arduino to prototype then made final units using just the AVR microcontrollers. Check out the led controller here: www.instructables.com/id/DMX-LED-Strips/
www.aliexpress.com/item/Wholesale-3CH-LED-dmx512-Controller-board-3-channel-DMX-512-RELAY-OUTPUT-LED-DMX512-Decoder-Relay/32379628423.html?spm=2114.01010208.3.10.t43y8x&ws_ab_test=searchweb201556_8,searchweb201602_1_10057_10056_10055_10049_10059_10058_10017_405_404_106_105_104_10060_103_10061_102_10062_412,searchweb201603_6&btsid=7b44008c-6d71-423f-99f0-5a671aff5b6d I got one and so far it's been good.
Much simpler than CAN, but developed around the same time. DMX lacks error detection. The newer RDM standard that is backward compatible with DMX has bidirectional communication and other enhancements. RDM wouldn't work fully with this unit because it requires bidirectional communication.
Not sure if it has proper isolation. Have a look at wires of the different sources touching each other, especially running through tight metal space. Another thing is that outputs have common ground which is half work done. And my final thoughts are regarding not sufficient PCB tracks isolation. Anyway, not trying to be a smarta**, just laying down my thoughts
You sound upset that it wasn't shitty! Ugh it's good! Damn it didn't get a defective item that exploded, waste of money! I was cheated! I deliberately bought the cheapest one I could find hoping it would be rubbish and worth the purchase
It's rather annoying that price doesn't necessarily indicate quality anymore. So many good and bad companies are willing to sell at a loss, just to get their brand name out there. A downside to capitalism.
Man, a cup of coffee and some Big Clive makes my morning PROPER! I'm not an electrician by trade but more by hobby and happenstance. It's so awesome learning from someone of your skill and knowledge level.
Ordered mine before I watched this video. Now I'm 110% glad I've ordered it!
I knew it! I found your videos by accident and have spent a week solid watching pretty much all of them. I work in the home automation industry so do electronics every day but have a back ground in live production. I did sense that you had something to do with this background and I was right lol. Good work.
God said: "Let there be light!"
And behold, there _was_ light. Because Clive had already been there and stretched all the wiring and installed all the light-fixtures. So it was just to flick the switch.
You who work with lighting have probablly neeewer heard that one before : )
Love these videos with random gear that I have no interest in or use of.
I learned something new today. +1 besserwisser stat to me.
Should start stripping down some more industry gear! Only so many variations of poundland things I can watch!
Cameron Marks The unfortunate part is that the industrial gear costs considerably more than a pound. So buying stuff just to take to bits would get expensive very quickly.
Cameron Marks thats more mikeselectricstuff -
+bigclivedotcom Good point, but if you scour the used sections of eBay, then you can find some interesting and cheap things.
Maybe you should open a PO box, but I don't know how well that'd do considering that you live in the isle of man :/
How about tearing down industry gear that has failed?
I'm an amateur radio operator, and wow, have I had my share of issues related to standing waves. Most issues for us hams are about the antenna itself, though, rather than the transmission line, and it's all about the resonant frequency of the antenna.
Usually we use 50 ohm coax, and then we use an antenna tuner, basically an LC match circuit, to match the impedance of the antenna to that of the feedline at the desired frequency. Most transceivers are quite tolerant, but simple homebrews could blow the final transistors when transmitting into an improperly matched antenna system.
Hey Clive awesome video! I work in the entertainment industry doing lighting and i see people using cheap 3 pin XLRs for dmx all the time and then they spend soo much time trouble shooting DMX errors.
Showtec tend to make some pretty solid gear.
Even Elation stuff is cheaper than it used to be, though...
I know nothing about the lighting industry, but that protocol reminds me a bit of the old 10BASE2 Ethernet stuff in networking from long ago.
EddyGurge 10Base-2 aka cheapernet doez use looping and termination. But it's single-ended signaling over 50ohm coax, while RS485 is differential over shielded twisted pair.
Almost 11 minutes without saying the "I" word. Well done.
The more expensive ones tend to have a micro in there that will rebuild the DMX signal, so that you have a "fresh" output signal on all the outputs. Passive splitters like this will not repair any signal degradation that occurs along the way. Active splitters will. In some cases, this can be useful. For instance in very long cable runs.
jaaasgoed I prefer to buffer it up well before it's been degraded that far. I'm slightly notorious for being lavish with buffers. The slight downside of the active units, especially the bidirectional RDM type is that if the processor crashes you either lose your data stream, or worse it can jam the whole universe it is on.
jaaasgoed You can do that with just a comparator, which costs about 50 cents.
+bigclivedotcom The "best" failure is when it takes down whole universe by sending some random shit during the show! Disco anyone ?
Fogger stuck at 100 % anyone?
Anvilshock Flames and pyros too?
If one of the mains transformers had been rotated 90 degrees it would've reduced any coupling between 'em ... Not a problem, just icing on the cake :-)
The part which you said that a 100 ohm or 120 ohm resistor being used as a terminator is used quite widely in data transmission. One example would be the connections from a PC to a monitor where you would have a power amplifier and a non inverting amplifier for the same data (the reversed polarities of signals would help in the interference issues and restoration of the signal, on the other end it is capped off as well with a resistor to prevent mirroring of the signal :)
I think that it is a connection from a pc to a monitor.. VGA type things.. I may be mistaking it with sound connections..
The most infamous "termination" horror stories in IT pretty much come from one of two things: 10Base2 Ethernet (or (shock-horror) 10Base5, for the *really* old fogies), or scsi. With coax Ethernet, you need termination on both ends, or things will go horribly and unpredictably wrong. With SCSI, *most* of the time you only need it on one end of the cable explicitly, because most SCSI cards included a terminator pack on board and mostly it was active by default... But note the qualifiers, if you forget to check it will be the one time things go bad - and then the consequences are data loss on your hard drive cable.
I was just a kid at the time, but I remember my friends dad 15 years ago or so talking about SCSI drives. I don't remember much about them specifically, but I remember that at the time they were quite a contender in terms of speed. Do they even exist anymore for the average joe on the consumer market?
Loren Husky Modern SCSI uses a serial protocol (SAS) that is so similar to SATA you can often plug SATA drives in. The SCSI speed for the past 20 or so years came mostly from hard drive factories only shipping their fast drives (10000rpm up) with SCSI connections, while insisting that SATA/ATA/IDE drives would only be available up to 7200rpm . Entirely artificial. Another benefit of SCSI was having up to 7 or 15 drives per cable with parallel versions, compared to two for ATA/IDE. The biggest bane of SCSI is that the cable making industry infested the standards process, resulting in too many different connectors being standard, unlike ATA/IDE which stayed with one connector in different qualities, all compatible. Even these days, serial SCSI (SAS) has multiple connectors with similar names, resulting in otherwise good webshops getting listings wrong and selling you a useless cable. But SAS top cable speeds exceed SATA cable speeds, making it the only option for some things.
In the same metal case, they now sell four different versions (with not that much price difference): this one, an 8 port version that has only 3 pin outputs (I guess that's where their disco roots are showing), and an RDM version of both which should mean they're bidirectional.
Nice bit o kit at a sensible price. A good find for sure! :-)
Thank you for all the informations :)
Hi, I have a problem on two of my DMX led-par. They don't respond on any command from my DMX-controller. They work correct when I use them with there own sound-program and Auto-program. But not on any DMX-channel. I have looked at your videos and are impressed about you knowledge!
The CANBUS protocol is quite similar to rs485 and a the voltage levels are very similar and I did build a interpreter on breadboard and I got it to work with one caveat: some data corruption occurred over long runs without a buffer similar to dmx I also prototyped one of those and the circuitry of this product is very similar 🤔
With canbus the lines have a relaxed and active state where they pull close to a supply rail. With RS485 it's a distinct polarity change.
@@bigclivedotcom yes it was one of those projects: just because you can do something does not mean that you should but my attitude is fuck it let's do it anyway
Could the MZ thing be some sort of zener ?
We had a large network where i worked for building access control, kept getting damaged by lightning impulses, so on my suggestion the company that supplied the equipment added 2 reversed zeners, and 2 fuses to each box (crowbar circuit), so maybe that's a double zener type device ?
***** A common way of protecting the transceivers inputs and outputs is the use of a PTC fuse and tranzorb (I think the diode things are tranzorbs). The PTC fuse would protect mainly against accidental application of DC from something like a miswired scroller cable.
bigclivedotcom Often TVS (transient voltage suppressor) diodes are used. They can withstand huge currents for short amounts of time. Tranzorb is just another name for it.
I was wondering why the connectors have four wires (five for the input section), but then you mentioned the LED's haha. You also mentioned it runs over twisted pair cable, is the screen a requirement or is it optional?
PuchMaxi1988 The screen is a requirement for open cable runs. The standard does allow for the use of CAT5 cable with one pair for data and another pair as the ground reference, but it requires a screened CAT5 unless it's run in its own conduit.
There are specific cables suited to DMX cabling that have a specific "characteristic impedance" of around 100 to 120 ohm. I don't particularly recommend researching characteristic impedance unless you want a headache. It's all to do with propagation of an electrical wave down a cable and how capacitance and inductance affects it.
The question that everyone wants answered is have the connected the earth up to the chassis? lol
Love your videos!
I was wondering the same thing, and yes they did. You are able to see it at 5:05
TornTech The earth was firmly connected to the chassis with an area of the metal buffed clean for a good connection, and the lug held on with a serrated washer and locknut.
bigclivedotcom At least some manufactures know what that weird green and yellow wire is for lol. good to see!
It would be interesting to see other items from this company to see if its all a good bang per buck or if its hit or miss.
Just on cost I found most decent buffer isolators are priced higher than many low cost consoles. Fount to do a long run from a console to a lighting rig, it is actually cheaper and better isolation can be obtained by using Artnet, E1.31, on Ethernet and have full transformer isolation on BOTH ends of each Ethernet cable by using off the shelf inexpensive networking switches and routers, plus you get multi universe distribution for less cost than a good quality DMX splitter. Seeing the splitters run from $600-$1500 each does not make economic sence when better isolation can be had with a $50 4 port Ethernet switch and several $120 6 Universe Artnet to DMX converters. The Ethernet standard has high quality transformer isolation on each port, data regeneration, handshaking,, retransmissiion, etc, that DMX alone does not have. Due to cost, higher multi-universe capability, and better isolation, I've moved to Artnet DMX over Ethernet instead of much higher cost DMX cable and Isolator splitters. Many quality consoles support Artnet out of the box, such as the Leviton Piccolo series. Artnet and DMX outputs can be used at the same time.
I got a Trancsession 4 way DMX splitter second hand that originally cost about £120. It is a poplar one and is rebranded by several companies.
We use RS485 at work, and we exclusively use little PC-Boards that passively split the signal into 4. Theres no reason I can think of why it should be different for DMX?
DMX has a bit rate of 250kbit/s (250kHz) and is used over long distances. It can't be split without proper buffering as signal reflections will potentially corrupt data.
RS485 is just a signal standard, your system may be low speed.
@@bigclivedotcom okay! Thats fair. We clock our data bus at 19200. Reliability is more important than speed.
Hola, realmente is a good video, felicidades.
Puedes hacer un video de como se puede medir una señal dmx en un osciloscopio?
Y que cambio produce el uso de una terminal DMX en la señal?
Muchas gracias, saludos.
i was inside a chauvet dmx splitter recently and it was identical to this one.
for cctv application 12v is the standard for RS485
Hi, im curious, do that Showtech DB1-4 spliter/booster have integrated 120omh termination rezistor on DMX input side.
And do DMX input side ground(XLR 1th leg) is connected to PE(chasis ground or from power in cable)?
Thanks.
Probably not the first to tell you but those electronics gets beat up a lot on the road. These cheap but handy solutions ends up without protection between heavy gear so that is probably why they do not use sockets for the chips. It would be "broken" after 3 shows...
dimlexavr Yeah, the stuff does have a hard life. I'll probably pop the lid on one of the PRG stock buffers to see how it compares.
bigclivedotcom Be prepared for circuit board broken around the mounting screws. ;) I have seen that a lot...
Is this an alternative to fiber optic lighting control systems for large venues?also at what point should I worry about using xlr cords for my dmx setups?
+AlbanyHauntCA Fibe optic is used for large amounts of channels over large areas. The point you should worry about your standard audio leads (if that's what you're talking about) is when your network length reaches a point where the lights start doing random stuff, or in the case of a professional event it's got to be proper data cable from the start.
+bigclivedotcom thanks! thats good to know. Also what kind of system would you use to run DMX in a dark ride or walkthrough atraction. I want to be able to to triger multiple scenes at the same time and also have those scenes trigger audio. Please tell me if that makes any sense.
love your videos!
+AlbanyHauntCA You can get the audio repeater modules on ebay. I'm not sure the best option for triggering multiple items. It's going well and truly into the area of show control. Gilderfluke stuff comes to mind.
Can we get a schematic of the transformers and how they're configured to be completely isolated? Also can you post the schematic for the power supply side: PTC thermistors, capacitors, ferrites, full wave rectifier diodes, and voltage regulators?
Thanks so much
DINKIN It's obviously bog standard textbook. 240V to few volt AC transformer. Bridge rectifier. Capacitor. RF bead and second capacitor. 7805. Add in PTCs, TVS , fuse etc. as needed. Make a complete second one like the first and stick em on the same board with an isolation gap between them, crossed only by the optocoupler.
Hmm outputs are not isolated amongst them?
+mikokuijn Not between the outputs. Just the input to output.
Why would you use a 5 pin connector for a standard where you only need 2 wires plus shield in the first place?
The original standard allowed for two networks on one connector, and it also avoids issues with the DMX being mixed up with audio cables which are XLR3.
And to be honest, they deserve it when they don't get away with using microphone cable, and things go horribly wrong.
thats a litle harsh
+jayja45 maybe that's what happened at the infamous Great White show.
Physics is harsh - use proper DMX cables.
drutfurgeson definitely not what happened at the great white fire. DMX is not super popular as a pyrotechnic firing control system. even when it is used, it is never the primary firing system. electronically fired pyro systems have a manual operator switch which must be set to arm. that's regardless of the fact that the building was not suitable for pyrotechnic displays. there never should have been any to begin with, even if there was the off chance someone had 20 years ahead of time pyro systems hooked up to DMX there, they should not have hooked it up in the first place. its not a funny joke either. a lot of people died horribly
If you're lighting a show with revenue in the thousands of dollars and up, sure. If you're a mobile DJ or a small nightclub or a state fair -- and you can get away with using 3-pin mic cable because you have 50 feet total cable and all of ten lights...
Seriously, NObody uses all five pins anyway. There's "proper", there's "good enough", and then "not good enough". If nobody is losing lives or (significant) money, it's perfectly acceptable to determine the difference by trial and error.
The electronics do not care, and are not impressed by "proper". They live in a world of "good enough" or "not good enough".
Does the device buffer both pairs of data pins, for use with (rare) equipment that does make use of all five pins?
No. Just the single pair.
Most of my lighting experience is with a home-made (not originally mine) 8-channel deathtrap box with standard household dimmers and NEMA-15 outlets, running on mains 110v AC with a power cord per channel running from the board at the back of the gymnasium to the stage at the front (lots of gaffer tape is used).
I've only used a DMX control system on a couple of occasions where the school's production budget was high enough to facilitate renting a proper lighting set (despite my attempts to persuade them to get our own set). They were all DMX-3.
Have you ever encountered a DMX-5 system that actually utilized the second data pair?
I have encountered plenty of systems to incorporate those pairs due to the fact it is part of the standard, however, I haven't opened them up to see if they actually use it or not.
If you're setting up a small lighting system, you'd probably be best of using a USB to DMX 3Pin, like this
www.ebay.com/itm/New-USB-to-DMX-Interface-Adapter-DMX512-Computer-PC-Satge-Lighting-Controller-US-/281730984904?hash=item419879abc8:g:ODgAAOSwT6pVihQK
Using freeware with a laptop/desktop which I'm sure the school can provide, and those splitters are much less expensive. Like this
www.ebay.com/itm/LED-Controller-DMX-8-Channel-Output-DMX512-Signal-Amplifier-Splitter-Distributor-/222254953371?hash=item33bf6d739b:g:1tAAAOSwmfhX39GV
As far as cheap lights within their budget LED's are the cheapest option right now, and for a basic small stage, you can light it quite effectively using a set of these for instance: www.ebay.com/itm/10x-86-RGB-LED-Stage-Light-Par-DMX-512-Lighting-Laser-Projector-Party-DJ-Disco-/301672148579?hash=item463d0fae63:g:oNQAAOSwU0RXHYvs
And the wonderful thing about those is they require NO DIMMERS, Simply power, and minimal power at that. So running the power is as simple as wiring up some standard NEMA power to a grid. With no dimming at all. I'm no electrician, but that isn't hard.
Focusing is dead easy too, just point. And after initial setup little setup would be needed as long as you set up each LED on it's own channel range and have a good way to deal with that, maybe upstage, downstage, centerstage, left, right ETC.
And that's how you make a dead cheap system. Would it work? Probably. Would you make a lot of admins and parents happy? Definitely, if it worked. And I see no reason why it wouldn't. And if it's not a professional stage, I think you'd not get any complaints. You could easily set this all up for much less than a grand, if you had a grid already. and even if you didn't just a way to mount them should suffice. Cabling and stuff would be the majority of your cost.
I didn't know they made USB-DMX controllers. That's quite handy.
As for the generic LED cans, they look easy enough to use, but given the price and lack of any kind of lens (or other spec data such as lumen output, beam spread and focal length), I'd say they're more for effect (disco/DJ stuff) and would be pitiful for stage lighting. My setup typically uses 12-18 tungsten filament flood lamps with typical wattage of 100-150w each. I also need something with a somewhat focused beam, of the kind a PAR can can provide so I can do discrete lighting zones. They'd be good for the school dance, certainly, but not stage lighting.
And anyways, I'm not doing the school's productions any more, I'm afraid. As much as I loved doing them, I just don't have the time any more.
Perhaps not stage lighting yes I agree, but you'd be surprised, for the cost its quite good! And for a small black box production that requires just lighting the stage, one could probably get away with it. With a bit of tinkering of course ;) But yes time is the ultimate factor. I have hardly any time to spend on non profit low budget stuff anymore unless its for my own home! Haha
how hard is it to make DMX devices, I can't seem to find simple low voltage DMX relays that don't cost obscene amounts like those from Doug Fleenor Design which is a shame because I would love to be able to solder in all sorts of cheap eBay lights to toggle on a console.
You definitely pay for something which is handmade in a small shop with some of the finest components in the industry...
If you have used Arduino, it's very simple. There are a few library's out there that'll do what you want. Connect a max485 into the arduino serial input and write some code.
I've made a double relay unit and also a 5xRGB led tape controller. Both have been very reliable over the last 2 years with approx 7-10 shows per week. The only issues they've had are all due to inadequate short circuit protection on the outputs - a conscious decision to save costs and space but I wish I'd used auto resetting fuses.
I used arduino to prototype then made final units using just the AVR microcontrollers.
Check out the led controller here: www.instructables.com/id/DMX-LED-Strips/
Instructables charges? It certainly isn't letting anything go without signing up :-(
www.aliexpress.com/item/Wholesale-3CH-LED-dmx512-Controller-board-3-channel-DMX-512-RELAY-OUTPUT-LED-DMX512-Decoder-Relay/32379628423.html?spm=2114.01010208.3.10.t43y8x&ws_ab_test=searchweb201556_8,searchweb201602_1_10057_10056_10055_10049_10059_10058_10017_405_404_106_105_104_10060_103_10061_102_10062_412,searchweb201603_6&btsid=7b44008c-6d71-423f-99f0-5a671aff5b6d
I got one and so far it's been good.
You mean daisy chain , not loop.
So basically this is CAN for lights?
Much simpler than CAN, but developed around the same time. DMX lacks error detection. The newer RDM standard that is backward compatible with DMX has bidirectional communication and other enhancements. RDM wouldn't work fully with this unit because it requires bidirectional communication.
I use 32universes of artnet..I have a few of these
and just so people may not know but dmx stands for digital multiplex
Once I accidentally plugged a dmx cable into a sound desk.... Welp it sounded interesting..
when are you going to be 100% sure?
Ah. Beware those who go around being 100% sure. The first time you say you're perfect, you no longer are.
Not sure if it has proper isolation. Have a look at wires of the different sources touching each other, especially running through tight metal space. Another thing is that outputs have common ground which is half work done. And my final thoughts are regarding not sufficient PCB tracks isolation. Anyway, not trying to be a smarta**, just laying down my thoughts
MZ6 www.dxmht.com/products/ptc-thermistor-mz6.htm
You sound upset that it wasn't shitty! Ugh it's good! Damn it didn't get a defective item that exploded, waste of money! I was cheated! I deliberately bought the cheapest one I could find hoping it would be rubbish and worth the purchase
Not upset. Just surprised.
@@bigclivedotcom hahaha I'm just bugging ya Clive! I love your videos by the way!
It's rather annoying that price doesn't necessarily indicate quality anymore. So many good and bad companies are willing to sell at a loss, just to get their brand name out there. A downside to capitalism.
"Like standing waves?" Seriously? You ever hear about RF Clive? Disappointed that you dumbed it down so far.