DIY DMX controllers?

[Steve Gase]

I saw RJ's mention of a future addition... what someone termed a DSC (Dumb String Controller) that apparently leverages the existing Active Hubs.    GREAT IDEA, and I can't wait for this to become available.

Maybe that addresses my next request -- or I am requesting something different.  I'd prefer not to have the requirement of an active hub in all situations.  It does consolidate the power distribution, so I like that, but there are times that I just want a simple DMX controller that I can daisy chain throughout the yard... maybe for illuminaries, or RGB tree ornaments, or strings that go along the roof-line.  Running lots of cat5 from a hub could be a problem.

So... I am looking for a cheap DIY version of a DMX, 3-channel controller. (DMX control and power in... common and 3 lines out...)

Up until now I have been using the $7 pre-built controllers -- and they work great.  I'd just like to have something cheaper that I can build on my own.  If I could spread $2 ornaments throughout the tree, it would be great.  ($1 for the controller, $1 for a couple pixels). Maybe $1 for the controller isn't possible, but I'm hoping for something better than $7.

Any suggestions?  ...something buildable from this community?  ...or from another community?

[crazybob]

I have no suggestions, but something like this would help me out also.

[JonB256]

Even if were slightly more than $7, I'd like a DIY 3 channel (or 4 for RGBW) controller that had RJ45 in and RJ45 out, plus  power in and out. 

[taybrynn]

In a way, this can already be done with ss nodes and a ssc ... Just skip these null nodes but use them as repeaters and don't program them.

If you used 5 nulls between each, you could turn a 100 node ss into a bunch of 3ch controllers with single signal and power and you could make each as big as needed.

If you think about running a 12v ps to each 3ch controller, this seems easier and perhaps cleaner.

The 4ch makes less sense to me because a 3 ch rgb on 100% gives white already.

[Steve Gase]

I don't want to open a can of worms, but I was thinking of a power-injector that added 12v to the start of the daisy chain.  and each element would take its power from that 'bus' and continue the power to the next element...  need more power?  add another injector later in the chain.

btw: injectors throw away whatever comes in on pins 3-8 and add NEW power to pins 3-8 on the outbound side.  elements pass both pins 1-2 AND 3-8 on to the next element.

so, after a run of 20 RGB elements on the DMX chain... and the 20 elements use up most of the 45 watts from the last injector, you  insert a new injector that gives your DMX chain a new 45w to work with.

Apologies to RJ if this is getting outside of the intended scope of DLA.  I'm hoping to convince you (or one of the other designers) that a cheap DMX 3/4-channel controller would be a great addition.

[chrisatpsu]

you sorta already have power injectors...  they're called the 4 port passive hub.

[taybrynn]

Right, those 4-port hubs give you the option of injecting and splitting or just splitting and using central power from the SSH.  I used a couple passive hubs with the 3.75a power supplies from Ray and they worked flawlessly.  And those passive hubs are just a pcb, some fuses, power connect and 4 cat5 jacks (simple).

I think a lot of the RGB world is using 5v and with that, you have to re-inject a lot just to keep the voltage usable at distance.

[rrawlings]

I actually right now have a design I am working on that would be that exact thing.  3 or 4 channel DMX controller that will have all you are asking for, give me a month and it will be finished.

[Ozmin]

I actually right now have a design I am working on that would be that exact thing.  3 or 4 channel DMX controller that will have all you are asking for, give me a month and it will be finished.

That sounds like great news.

Bill A.

[chrisatpsu]

if you want dmx control...

to power ac, the ssr4 does that
to power dc, they have those cheap ones like you can find at holiday coro
to power dc, and run from the pixelnet equipment, rj hinted at something in the works.

a company i worked for had the philosophy of "if everyone else is building a 1/4"bolt, it doesn't make sense to start making a 1/4" bolt.   instead make something else that isn't being made."

[Steve Gase]

I actually right now have a design I am working on that would be that exact thing.  3 or 4 channel DMX controller that will have all you are asking for, give me a month and it will be finished.

Sign me up for the beta!   thx!

[Slite]

I actually right now have a design I am working on that would be that exact thing.  3 or 4 channel DMX controller that will have all you are asking for, give me a month and it will be finished.

Sign me up for the beta!   thx!

That! 

[Steve Gase]

if you want dmx control...
...
to power dc, they have those cheap ones like you can find at holiday coro
...
instead make something else that isn't being made.

I certainly get your point.  Right now to get what I want I need to buy from Ray (with the overhead of shipping from China) or buy from Harrison or David -- I like the guys, and would definitely buy from them again -- but I'm thinking 60-100 controllers, and I'd prefer to pay $60-$100 instead of $500-$700 or more.  So, I'm looking for cheaper 1/4" bolt. 

[tbone321]

While I see your point, I really don't see where you are going to get them for much less than $7.00, even if you build them yourself.  The real advantage of building them is then you can control the configuration of the hardware so that they can meet the output demands that you want as well as the firmware that they use where you will not be locked into a special programmer or software to set the start channel.  You could also write firmware to make them either a DMX, or PixelNet device wthout the need for converters between the different protocols.  These advantages WOULD make them worth looking into, not just the price because I doubt that you could cut the cost much here.

[wwwgator]

"You could also write firmware to make them either a DMX, or PixelNet device wthout the need for converters between the different protocols.  These advantages WOULD make them worth looking into, not just the price because I doubt that you could cut the cost much here."

That would be HUGE advantange....being able to select control protocol using common hardware

I kind of like the BobCat servo, even if I dont use the 8 PWM outputs, It also has 8 channels of dmx output control ability


my $.02