help required with polywheel 20 and dmx control

[dave321]

i need a liitle help trying to understand how to
1)connect a polywheel 20 diffraction wheel up so it can be controlled through the dmx on qm2000.net.
at present i'm just using a manual 10k pot to provide the analogue voltages (see attached pdf).
i think i may need some other dmx board to connect it to, although there is an onboard signal to flip an opto isolator to re direct the beam.
2) set up in qm2000.
i've contacted laser visuals but so far no reply.
please try to keep any explanations simple, i'm no electronics wiz like some of you guys.

[Stuka]

I have the same thing - You'll need a basic DMX decoder board that provides a 0-5VDC output that varies with the input DMX signal. Laser Visuals has a "4 Channel DMX Controller for Poly 20 Kit" for £ 75.00 that is actually one of these decoder boards with 4 separate 0-5VDC or 0-10VDC outputs. Similar boards are also available from Northlight Systems in the US: http://home.att.net/~northlightsystems/dmx512decoder.htm.

Even if you don't buy their boards, you might want to download the free manuals for Northlight's DMX decoders - they include a great general reference section on DMX wiring. Highly recommended!!

High-end boards with multiple high-current outputs are available from Pangolin and others, although these are probably overkill if all you want to control is the Poly-20 kit.

I don't have a QM board (I have an FB3, which requires a separate DMX device to control DMX equipment) , but the hookup should be something like this:

DMX output from the QM board will connect to the DMX input on on the decoder board. One of the 0-5VDC outputs on the decoder board will connect to the "Analogue Input (0-5V)" on the Poly-20, which is Pin 1, Connector A on my Poly-20. You'll probably be able to use the same power supply for the decoder board and Poly-20, which will take care of the requirement to have the power grounds tied together between the Poly-20 and decoder boards.

After the connections are all made, you'll use your laser controller software to send the appropriate DMX commands through the QM board to the DMX decoder. These are turned into the 0-5VDC voltages that are fed into the Poly-20 kit to determine the various stepper motor positions for the Poly-20 grating wheel.

Good luck with the project!

[dave321]

thanks for that, i think i'll chase lv up.......cheers
dave321