Thread: 7-pin DMX
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Old November 17th, 2007, 06:22 PM
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Default Re: 7-pin DMX

Quote:
Originally Posted by len View Post
To be excruciatingly precise, the ONLY cable that is truly dmx is 5 pin twisted pair shielded. This according to the USITT standard updated a couple years ago.
4 pin scroller cable is not dmx, although it is used in lighting. As is 3 pin xlr, and perhaps 6 or 7 pin. Or cinch-jones. And all the others. Theoretically, 3 conductor extension cords could carry dmx data. So while it is possible that any cable carries a dmx signal it is not truly dmx standard unless it is 5 pin xlr twisted pair shielded cable.
The loop hole to the standard was that the manufactuers could put 3 pin on and call it DMX if they supplied an adapter, so people just put on the 3 pin and forgot about supplying the adapter. The real deal was that production houses did not want to stock an extra cable when they had plenty of 3 pin connectors and cable laying around.... even though hardly any of it was meant for data.

Before anyone says it... RDM was originally thought to use the second pair but because so many fixture don't have access to the second pair they were able to cram RDM into the first pair along with DMX data.

It has also been said that you can run DMX through a barb wire fence... would you want to... no... but you could.
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