Applications for Northlight DMX512 products.

This page has information showing basic ways to use our DMX decoders and encoders for lighting and special effects.

Click here to see photos sent in by users.

Using Solid State Relays with Northlight Decoder Boards A list of acceptable types
Controlling Hobby Servos with 0-10 volts How to use the 8 and 24 channel decoders to control hobby servo's.	Analog encoding. Turning switches, pots, and sensors into DMX512.
Pulse Width Modulation. Use 0-10 VDC to dim LED's or control motor speed.
Simple Oscilloscope trigger circuit for DMX signals.	Light dimmer circuit.Simple light dimmer circuits using 0 - 10 VDC control.

RECOMMENDED ENCLOSURES

The 24 channel Decoder fits in a PACTEC plastic enclosure, part # CM5 - 200. It available from many mail order distributors or can be purchased online from PACTEC.
The board mounting holes match up with the molded in mounting bosses in the PACTEC box.
Available from MOUSER part #616 - 64025 - 510 - 000 cost is $7.69 in signle quantitys.

The 8 channel Decoder fits in the PACTEC CM# - 150. The board holes do not match the mounting bosses so 4 - 1/4" spacers will be needed.
Available from MOUSER part # 616 - 63000 - 510 - 000 cost is $7.29 in single quantitys.

Using Solid State Relays
Solid state relays suitable for this application feature low input current, zero crossing turn on, and low voltage(1 volt) dropout. Either SCR or TRIAC are suitable.
Random turn on are not recommended. This is strictly on/off. Not a lighting dimmer.

Acceptable types Not acceptable

Crydom HD series    HD6025 - HD60125
Crydom D series      D1210 - D1240, D2410 - D2490
Opto 22                  120D10 - 120D45
Opto 22                  Z120D10 - Z120D45 Any Crydom with a -10 suffix   D1210-10 ect.
Any Crydom with an A prefix   A2420 ect.
Crydom CS              CS2410 - CS2490
Opto 22                   240D10 - 240D25
Any Opto 22 with an A in the number

Example circuit board for 8 solid state relays. Note this board showns the silk screen. To download an actual size 300 DPI scan of the board without the silkscreen, in PDF format, click on the image below. Also note this view is from the top looking through the board.
If you use LED's be sure they are low current type, 2 mA max current.

Photo with 8 channel decoder

Hobby Servo's
Turn DMX signals into mechanical motion.
Generally hobby servo's require a pulse having a variable width from 1 to 2 milli seconds, with 1.5mSec as the center position.
The schematic below is a simple voltage to pulse width circuit.

PARTS:
R1   100K OHMS 1/4 W                R2   47K OHMS 1/4 W
R3   33K OHMS 1/4 W                 R4   100K OHMS 1/4 W
R5   1K TRIM
D1   1N4148 / 914
C1   .22UF                                  C2   .01UF
IC1 LM555

It doesn't get more basic than this, all components are fairly common. The timer is set up to output a variable high pulse,1 to 2 MSec. and a long low pulse,20 MSec. Do not change the value of C1,R4. The trim pot is required.
The main draw back is that this circuit is not perfectly linear.

Scope trig
This is a simple O'scope trigger circuit for checking DMX signals. It is based on a 4528 CMOS monostable multivibrator.
The "trigger" pot is adjusted first, untill a short pulse is generated near the end of the "BREAK" portion of the DMX signal. Then adjust the "delay" pot to zoom in on a portion of the signal. On DMX signals with few channels it works to trig the scope on the "trig" output, rather than the "delay" output.
This circuit will not work well on DMX signals where the "inter frame time" is as long or longer than the "break". This is a legal condition, but doesn't show up to often.
It is best to keep this circuit "floating" by powering it from a 9 volt battery and a 78L05 voltage regulator(not shown in schematic).

To download this Zipped schematic just click on it.

Photos sent in by users:

Encode32 installed in an Arri board, La Coruna Spain.

Lots of room for the extra transformer and board.

This board is in good condition, just right for an upgrade to DMX.

Close up of the installed board.

2 - 24 channel decoders installed at the "Blackfriars Theatre" in Rochester, NY .

1 transformer for each board.
Fuses and strain reliefs all around.

Acceptable types	Not acceptable
Crydom HD series HD6025 - HD60125 Crydom D series D1210 - D1240, D2410 - D2490 Opto 22 120D10 - 120D45 Opto 22 Z120D10 - Z120D45	Any Crydom with a -10 suffix D1210-10 ect. Any Crydom with an A prefix A2420 ect. Crydom CS CS2410 - CS2490 Opto 22 240D10 - 240D25 Any Opto 22 with an A in the number

Lots of room for the extra transformer and board.
This board is in good condition, just right for an upgrade to DMX.