Does anyone else find Clive's videos relaxing? I like to chill with a drink and watch his long videos even though I know nothing about electronics. I love his sense of humor and the weird things he shows off though.

@maxximumb

8 жыл бұрын

Yep, I'm teaching myself electronics and originally started watching Clive's videos to learn stuff. Now I re-watch his videos to chill out. They are better than a lot of the repeats we get on UK TV.

@meteorshower8160

8 жыл бұрын

Glad I'm not the only one who loves his videos yet has a very small knowledge base of electronics :)

@UnexpectedSensation

8 жыл бұрын

yes and informative :)

@ahettinger525

8 жыл бұрын

Yes, I've disappointed myself multiple times by falling asleep listening to Clive.

@68MalKontent

8 жыл бұрын

I wrote this before - I find Clive's wit and mellow Scottish accent very soothing. I use it as an antidote for Dave (from EEVblog), who has an aggressive Australian accent and an annoying manner of speech :) For me the prescribed dosage is 3 Clives per one Dave :-D

Hi Clive! I'm really interested in lighting stuff, and I'm sure others would really love it too if you did more lighting equipment breakdowns like this.

circuit seperation is so important ,im so glad good motherboards have a isolation line between the onboard DAC componants

Surprisingly good quality inside, would be pretty easy to suck off that second bridge rectifier and add another dc in jack to make it fully isolated.

Just wanted to say thanks for making some of your PCB's available online, got the snowdrops and LED flower PCB's in the mail today, time to track down a suitable power supply and make things!

"That's tacky" - Unintentional pun of the year award goes to Clive... :P I still find DMX to be a mysterious thing, volunteering at an amdram small theatre & working the lights it was all old transformers, rubber cabling, & a mostly analogue desk (did have basic electronic functions like an auto-fade so you could drop the lights quickly on the board, but they'd fade out slowly, that was about it!), then they changed to DMX to upgrade it all, new programmable desk (so program in the scenes lighting & press a button during the performance to change scene, no fun!), LED & halogen lighting, new cabling that I wasn't to touch, it lost its appeal to me, I liked the old equipment, playing sparky cable roulette there was fun when moving lights about (fully against all H&S regs I'm sure) to set them up for productions, but oh well, sad thing is the old lights they had there are worth a fortune now cos of people living in studio apartments who buy retro theatrical lighting for that vintage look...

I actually have this exact one. Works quite well! Most I've ran with it is four lines out with around forty various lights in total.

Surprisingly well made circuit board and it wouldn't be much of a problem to just desolder the bridge rectifiers and feed the two circuits with different power supplies to complete the isolation.

I enjoy these videos way more than I should.

Just ran one of these for a week long gig in the desert, worked a treat :)

Those 2 rectifiers will separate the ground loop provided that the voltage differential is less than the input voltage. So, it doesn't make it safe against an exploded transformer, but it will (almost) decouple the 50Hz hum.

Thanks for posting! I really like the explanation, and now I’ll buy this dmx splitter

Love the pro lighting videos!

I've been using this for ages, works well! Thanks for the video

Damn, Clive, you're really booming! It feels like just a month ago you had ~80K subs, and now you're at 140.

not many Mux and Demux videos around. Applied for a network engineer job a while ago and looked into it all. Interesting stuff. Missile guidance systems and Seeker heads are very interesting too.

Mr. Clive. You need to get yourself a Post Office box, a 'mail bag' upload schedule. I got, literally, a metric tw*t load of electronic doodads you'd just go nuts for. Disassemble to your heart's content.

That photo quality was so good I thought I was looking at a large PCB until you drew on it ha

I would LOVE to see a full laboratory test using all of the kit.

"...when something goes wrong with DMX it's like 'Disco central.'" I mean, the Reggae thing worked for Snoop Lion -- can you blame DMX for trying to bring disco back?

@stephenoliveau

8 жыл бұрын

i guess not... but i can blame him for the atrocious recording quality in a good bit of his music.

@WafflesASAP

8 жыл бұрын

Stephen Oliveau lol, fair enough.

well this video, and the mention of getting a quality power supply probably answers the question as to why my Thomann and Strand branded DMX buffers/isolators have 240volt inlets, with the PSU inside, thus preventing it being powered by a bad external PSU.

I have one of these. Works pretty decent.

I have one of these and it works well. I just wish it had a power and dmx status light on it for diagnostics.

There is so much space in the case, you could easily mount a secound power input, break the traces of one of the supplies on the board and solder a pair of wires to the second input.

Great video thank you was thinking of getting one. As I find dmxing easier this way than daisy chaining

Good morning, Clive. Love to see a video up in the wee hours, but you have a song about that, don't you? lol 2 o'clock in the morning...

@TerrySterling-Thatguy

8 жыл бұрын

It's not 2 yet, Central Timer

@PeakeOfficial

8 жыл бұрын

Now it's almost 3 :D

@maicod

8 жыл бұрын

he plans his videos so Americans have their Clive meal during their evenings :D

Also, at that price, I'd buy the unit merely for the box fitted with all of the XLR outputs as a stage patch box.

@mr.berlingo8211

4 жыл бұрын

Screening?

Clever guy love your vids Clive

I purchased a beamZ S2000 smoke machine a few days ago, it is a beast, has LED lighting, fires smoke about 15-20ft in air and is DMX controllable :o

If it's got AC going in, and 2 separate rectifiers my guess is that that at some point in the past there was meant to be an isolation transformer in there.

Rapid Electronics and RS Components are trade only and are not available to the General Public. In Ireland we had Peat's of Parnell Street for components and hifi. They have closed their store in Parnell Street and now THEY are trade only.

Hi Clive Could you do a video on how DMX lighting systems work please ? would make a very interesting subject

@kathrynwhitby9799

3 жыл бұрын

agreed

Ground differences are ALWAYS present. We cannot avoid them. Power cables act as transformers that induce currents to ground prong so you cannot eliminate ground voltages between grounded electric equipments. Eliminate grounds connections means serious electrocution danger. (There is a good text if you like, easy to read "UNDERSTANDING, FINDING, & ELIMINATING GROUND LOOPS IN AUDIO & VIDEO SYSTEMS" written by Bill Whitlock, you can find on Jensen transformers site).-- In this case we try to feed a clean DMX (or audio) signal to the equipments. The opto isolator at the input is a good way to RECEIVE a clean dmx signal using the pseudo balanced (or fully balanced if the dmx controller out is fully balanced) cable. A star connection to different dmx equipment (as is this splitter) always create ground loops because connects together the equipments grounds at the outputs of the splitter via dmx cables. The only way to not connect equipment grounds togheter shoud be an opto isolator at the input of each MAX485 and a separate (not grounded) power supply for each of them. Or one only power supply and a transformer on each output. Obviuosly these are expensive methods. Fortunately DMX is not audio signal and is inherently protected by his "high" voltage (compared to an audio signal) and by balanced cables. -- I use this splitter in a theater to receive the dmx signal after 50 mt of dmx cable and feed 2 different lines of dmx fixtures. It regenerates dmx signal and avoids overload dmx connection splitting it with different buffers on the outputs. For the price is more than i expected.

If that board was glued in, methylated spirits (denatured alcohol) works really well for removing hot glue. No idea how it works, but just by putting a little on so it gets drawn in and under the blop of glue and it comes right off after about 30 seconds.

here in Belgium red was commonly used in the old days for ground wire.

Would love to see a large rig on a dodgy signal. My rig only has 13 effects on a DMX network and I can confirm that berserk is no exaggeration with only that many.

Well, it doesn't look like it would play well with RDM. But I suppose Christmas tree lights and LEDs for use in architectural lighting probably have never heard of RDM. So as a simple buffer in a small setup it will probably work fine. It's likely this was intended for luminaries that are running on 2-prong isolated wall warts, so it may be that the only real system ground will be at the controller, if that. Since this thing would probably be at the controller too (so you can do a star network) it may never see a ground differential between any of the outputs.

Curious unit. First clue it's not exactly high-end is that it's doing DMX over 3pin XLR connectors, not the usual 5pin. As to the power isolation; it might be quite easy to fix that by the addition of any of those 5V DC isolator modules made by Murata et.al. You could easily fit one of those inside the case and feed its (isolated) 5V output to the DMX input side. Whenever I do DMX that's usually the power isolation I go for.

Have a good Tynwald day Clive.

I have often no idea what you're talking about.. but somehow I still find it interesting.

Yey, 1000'th like! I guess it wouldn't be too hard to add another power input, considering how nice that box is.

The Problem is that all the 8-output DMX connecters are Junk the 3-pins sockets are not soldered to the back of the connector Luckily for me I found one in the DMX cable connector & I found that the Dmx Sockets are two pieces & they have a Sleeve (Socket) inside the connecter & they are just a VERY loose press fit to the back of the connector & Most Pins, Sockets are one solid piece & this is a very strange design & Wow! this being a Very Loose connector could cause all kinds of problems I even cut the connecter apart to verified it! so I replaced all 8 of the output connector & it works Great now

@EscapeMCP

7 жыл бұрын

Neutrik??? (FTW!)

@musicstevecom2

7 жыл бұрын

I Bought a bunch from E-bay "3-Pin XLR Jack Panel Mount Connector" it better to pick out the ones that are the same Diameter of the DMX unit holes the last ones I bought were to big so I had to drill out the hole

@musicstevecom2

7 жыл бұрын

Better to pick one that fit the Hole or you will have to make the Hole Bigger

So, solder in another power input directly to one of the bridge rectifiers and you're golden? Seems like a really good alternative for temporary installations.

It isolates the signal from the desk from the lights, so if the lights backfed voltage for whatever reason surely the desk would be protected?

They work a lot better after I fixed them all by replacing all the 8 DMX output connecters w New ones it was a Lot of work but worth it & still a good Deal,,,(I use a Bunch of Them which makes setup for live shows quicker & less cable runs and in Parallel)

The proper way to isolate the power supplies would be transformer coupled DC-DC converters e.g. a TRACO unit or one made from discrete parts. But that would likely push the price up. I may be able to send you the PCB from an industrial fully isolated RS485 converter (KD485) but it may have to be a faulty unit, I usually repair them but it's not always worth it.

Wow, that box is identical to a project box I bought off Amazon recently. It's really telling that they used hot glue instead of the mounting posts.

I fall asleep to this guys voice ~

@guitarstitch

6 жыл бұрын

I do to, from time to time. Soothing.

Most serious light/sound/stage companies usually buy proper DMX splitters from Martin, etc. You usually don't want to gamble on neither the power supply or the actual DMX splitter itself :P

so if had the correct XLR plugs on it (5 pin not 3 as specified within the DMX standard) would it be compliant with the standard?

3:26 - glue is tacky you say? hmmm... ya could be. ;-)

@XOIIOXOIIO

8 жыл бұрын

Glad I'm not the only one.

@jameslawrence8734

8 жыл бұрын

The problem was it was still tacky that long after assembly.

@KennethBrudzinski

8 жыл бұрын

"pun intended" Haha

3:27 - Glued in... Tacky... I see what you did there!

They're using lipo battery cables balance cables I've seen the red, black, yellow like that on ebay

I find it interesting that it seems to use Cannon Plugs to plug the light control cables in since that's what microphones use. Also, what are those little white three-pin connectors called that plug into the circuit board? I see those all over the place, mainly on the little rechargeable battery packs that those hand-crank emergency radios use.

@1973retrorabbit

7 жыл бұрын

Fixy Clary it's using the standard sockets that DMX lighting uses, to provide compatibility. There would be no point using anything else.

Just a question, are the outputs of those bridge rectifiers commoned in any way or are they both isolated from each other ? If they are isolated the cct may well be pefect without using 2 external supplies.

That's a nice little project-box. is it available as a non-drilled blank, I wonder.

@gordonlawrence3537

8 жыл бұрын

Banggood has similar for about £5.

@junits15

8 жыл бұрын

yeah I'd like to know this too

Seems like you could quire easily mod this unit to separate the power supply for the input chip, right?

Noob question: do you have to have some kind of special power supplies if you were to make this fully isolated if you were to disconnect the rectifiers from each other, or would any two supplies with their own transformers, rectifiers and smoothing caps work? i guess capacitive droppers are out of the question as they are actually referenced to the mains they are connected to

Hm, perhaps they got a young graduate (or whatever they have in China) to design it, and he did it by the book, or by the data sheet. Where the data sheet showed 2 power inputs, he just commoned them, and was pleased to see it worked. If you needed isolation it'd just be a matter of desoldering one of the rectifiers right? Ideally the one feeding the input circuitry. Then as a bonus you could wire in a lower-voltage DC supply so the 78L05 wouldn't be working so hard. I'm surprised at how nice it is, I was half suspecting a load of resistors and nowt else, maybe a couple of transistors or an opamp or something to drive the outputs all paralleled together. This is pretty much textbook, literally I think.

Those connectors look like the ones in 3 pin computer fans, which use these colors. I expect that due to economies of scale, that particular color arrangement is the cheapest.

Would it be hard to split the power into two supplies so it is isolated?

Full isolation is just an illusion. All DMX equipments have a ground connection that ties one to another indipendently by the dmx cable. The point is that dmx cable is balanced and the opto isolator led sees the voltage difference between dmx pin 2 and 3 with absolutely no reference to ground or earth. It's like pseudo-balance in audio cables (ex. Shure radio mics do it). Doing so it can cancel common mode interference and ground loop problems.

@bigclivedotcom

5 жыл бұрын

The primary benefit of isolation is when a rig spans several power sources. It avoids issues with ground differences.

Ah DMX, my arch nemesis :p

lol "I'm going to have to pull this board out of here", as if we didn't already know it was inevitable. ;)

Would you recommend to buy this for a little theatre scene?

been tearing my har out troubleshooting randm flashing/twitching of lights in a venue. been fine for a while. would come in and it would be fine, then other days it happenns. im not a lighting tech, recently discovered that dmx cabling is different to audio xlrs, so thats 1 issue, then found out that after certain amount of fixtures need a bufffer. we have 16 movers, 14 led pars... i never installed the cabling, did give instructions but it wasnt followed, the pars got installed first and wired up, then movers were added, pretty sure instead of goinng from first closest light and going round, they just wennt from last light.... cabling far too long

"...glued in? Well that that's a bit tacky." LoL I see what you did there ;-)

hi clive good day, can i use a 18.5 VDC 3 amp adaptor on this unit?

If you run out of items, tearing down an inkjet cartridge or testing those refilling kits would make for some good viewing.

@RonNewsham

8 жыл бұрын

Don't drink the ink though!

@sloppyengineering

8 жыл бұрын

It may make his poop spangly

Haha yes, I remember "cool lighting effects" comments from the cast whilst giving them the side eyes and trying to fault find a bad dmx rig

@paulgascoigne5343

8 жыл бұрын

Still.. I don't miss the huge wall rheostats of the old days that used to smell like an electric fire and used to get old and cause interesting lighting effects on their own accord. So dmx definitely wins.

Why does it need a bridge rectifier if you supply DC?

I'm a musician among other things. I've had several DMX buffers which gave me nothing but headaches. Now I know why... That said I've recently gone to a wireless system. I don't know how my system would fare in a large installation because I don't know the actual range of my transceivers. I use a Chauvet WDMX wireless transmitter. and the corresponding Chauvet D-FI Hub wireless DMX light transceiver to control the lights directly. Now the manufacturer says that the transmitter has a range of around 500 feet. I've never tested them at that range as I don't usually position them anywhere off stage. I'd be curious about your thoughts as they are rather expensive being approximately $430 for the transmitter and around $100 for the receivers.

If the inductor of te buck converter is a transformer the two circuits can be Isolated. But that doesn't seem to be the case here.

Can you do cheap MIDI-USB adapters?

caught one, nice and early for once

Just thinking about it in my head, wouldn't the 2 bridge rectifiers give you "sort of" isolation between the 2 separate DMX grounds?

@bigclivedotcom

8 жыл бұрын

It would probably block very low voltage differentials like 1 or 2V.

Unless the switching supply's output is isolated, then both supplies aren't properly separated.

Based on your description should I treat this product more like a hub/splitter? Meaning, a convenient way to install cable by home-running vs daisy chain. Lastly, should each of the 8 outputs be terminated with a resistor at end of line?

@bigclivedotcom

7 жыл бұрын

Yes, each run should be terminated with a 120 ohm resistor.

I need a Big Clive T-shirt that says "thats Quite Interesting, Thats quite interesting Indeed"

"Is this circuit board glued in? Well that's a bit tacky!" -- Pun Master 5000 :)

Even the QTX DMX-D8 for about 64 UKP is fully isolated...

Would the supply have been a DC type, or maybe just an AC transformer plug pack?

@JasperJanssen

8 жыл бұрын

Answering my own question, but looking at the eBay ads: almost certainly intended to be powered by the same 12vdc or 24vdc supplies being used to power the RGB led strips this will be used with.

Maybe adding a quick sketch of the schematic - either on paper or a white board - would give some clarity to your reviews?

Excuse the potentially stupid question... if its already a DC input supply whats the need for the bridge rectifiers?

@rshperformance4127

5 жыл бұрын

polarity doesn't matter

@resneptacle

5 жыл бұрын

@@rshperformance4127 I noticed you find that on many lighting or audio related equipment, I wonder why...

I lake dis channel and I'm luring a lot from jou

each output should be optically isolated from the other

I'm surprised you didn't comment on the fact they used 3-pin XLRs instead of the more common 5-pin. (I know, there's a fair amount of lights these days that come with 3-pin connectors, but they're not all wired the same. Much safer IMO to use 5-pin everywhere and use an adapter that comes with each instrument to go down to the right pinout for that instrument.)

@JasperJanssen

8 жыл бұрын

The point of three pin is that it's cheaper and the cables are cheaper, so it seems unlikely that the majority of the fixtures that use it would come with an adapter to five pin. I mean, a given shop could do that as a matter of course (but it's easier just to replace the XLR outs), but I don't think it's normal.

@CoolerQ

8 жыл бұрын

+Jasper Janssen Cables are not actually cheaper. Sometimes people cheat and use microphone cables for DMX, but because they're not twisted correctly, they cause similar hard-to-diagnose issues with flickering/disco-style effects due to interference. Using 5-pin cables is a great way to help ensure you're actually using a DMX cable.

@JasperJanssen

8 жыл бұрын

Quentin Smith like I said, three pin XLR cables are cheaper, because you can easily use crappy mic cables instead of proper 120 ohm shielded twisted pair. Plus proper Dmx cables actually connect both pairs even though only one is used, which means you need twice as many center conductors. Plus the plugs and sockets actually are significantly cheaper on three pin than on five, because they're used on audio runs in great volume.

Can anyone (+bigclvedotcom) explain the point of the bridge rectifiers? The case suggests that the power supply is DC - I'm confused.

@bigclivedotcom

8 жыл бұрын

I think the PCB is probably multi use. At the very least they will provide automatic polarity correction on the input.

@AdamWelchUK

8 жыл бұрын

+bigclivedotcom Thanks. Makes sense.

@emiledarius1995

3 жыл бұрын

I've seen some gear using a supplied external PSU with an AC output (higher than 12V) so rectification is needed on the board inside the gear. I can't recall if using a DC PSU will still work the gear properly..... Telephone equipment (UK's BT) often used PSU's outputting AC....

Could you draw a circuit diagram of it please?

3:30 the puns are real.

uot puot? ha! love the channel!

DMX gon give it to ya

how are surface mounted capacitors even possible. how much capacitoryness can you get in one of those tiny things? surely they cant have as much as normal size ones can they

@bigclivedotcom

8 жыл бұрын

They cram a lot of capacitance into them.

Hi Clive, I hope you don't mind the slightly off-topic question, but you seem like the best person to ask. I'm planning on installing some home automation gear to control my upstairs lights. I want to use dmx dimmer packs, the type with cable terminations, opposed to lamp sockets. Each channel will control a room's lighting. I want to power each pack from the radial circuit for the upstairs lighting (as this will no longer be used, as the packs will distribute power). Do you reckon I'd need another DB secondary to my main consumer unit, with an RCD for each dimmer pack? Thanks :)

@bigclivedotcom

7 жыл бұрын

You could power a multi-way dimmer rack from a single original lighting circuit breaker. I tend to recommend traditional wiring if possible as specialist wiring can make life difficult in the future for "ordinary" people when the control system fails.

@JoeRKsChannel

7 жыл бұрын

bigclivedotcom interesting. Thanks! Keep up the great videos :)

So every one of the 512 channels can make a light do something else (at the same moment). Does it mean every one of the 8 outputs just copies the same 512 channels ?

@JasperJanssen

8 жыл бұрын

Yes. The controller (lighting desk, pc hardware interface, whatevs) merely sends out data frames with one start byte, then (up to) 512 data bytes each containing a value from 0-255, and then repeats. So if you set your RGB led strip to be channel 500-503, the lighting desk is going to send a start byte, then 500 bytes of 0 for channel 0-499, and then your four desired bytes, which the lighting fixture can interpret however it wants. Traditionally, 0-255 maps onto 0-100% of a dimmer channel, but sometimes it maps onto 0-360 degrees of a moving head direction, or onto one of eight gobo slots, or a color, or.. Etc. And per DMX universe, all that is happening is that there is one sender which is transmitting those 512 channels of one byte each, and there are any number of receivers which are taking any number of those channels and interpreting them as whatever. Hence why a subtly-off data transmission is such a problem.

Cool

Does DMX require termination seeing as it's 485? Does this sit the same at the end device in the multidrop configuration? Is it the same nominal 120R value?

@bigclivedotcom

8 жыл бұрын

Yes. But many just ignore it until problems occur.

@Motorman2112

8 жыл бұрын

"ignore it until problems occur" can also be applied to "mic cable will be fine". :) I'm an audio guy and I'd love to see more videos on live production gear and industrial power.

is this board glued in?... that's a bit ...... TACKY!!!! genius

Not sure why people are really wondering too much about the isolation of power supplies on such a cheap unit not intended for professional use. Strictly speaking it doesn't even conform to the DMX standard as its got 3 pin connectors when the standard specifies 5 pin connectors. $0.02

@EscapeMCP

7 жыл бұрын

Most lights don't conform either. It's a bloody pigs ear of a mess covered in junk!

Quite an interesting device. So it basically just amplifies and repeats the same signal. I was thinking it would work more like a network switch, where it could be accessed and it would assign subaddresses to things plugged into it. Didn't know DMX was such a simple standard. Also, is DMX one way, or two way? One question @ 4:25. Why would ground be Yellow. Green or Brown would be ground if anything. Black if the power supply is ground referenced. Yellow is almost always +12VDC on logic stuff, some sort of signal wire or in the case of AC, it's hot.

@bigclivedotcom

8 жыл бұрын

The UK earth/ground wire is a green and yellow striped wire. Plain DMX is a very simple standard, but you also get a modern version called RDM that can communicate both ways and also allow the assigning of addresses to lights remotely.

@theLuigiFan0007Productions

8 жыл бұрын

bigclivedotcom Makes a lot more sense now why that one power supply of mine was colored in what I thought was very nonstandard. Wired hot to ground the first time around and that wasn't very nice when I went to switch it off and unplug it see what was wrong. A bit tingly to say the least. I do think I read up on those colors afterwords but I appear to have forgotten once again. Quite interesting about the different types of DMX, might read up on that a bit. Thanks for the info.

@FilipWahlberg

8 жыл бұрын

Yes, DMX512 is a simple protocol indeed, which is great since you can use the cheapest microcontrollers to decode it, meaning cheaper stage lightning. It also delivers its data deterministically, i.e. you can be sure that all 512 channels are updated at least 44 times each second (which happens to be just enough for our eyes not to perceive flicker). And should a bit error occur, it will be visible but at least corrected immediately. More modern protocols have much higher throughput, more channels, bidirectionality etc, but lack some of these basic features.