Avo Decoders For FD

[leofric]

I am getting an intermitent problem with the Avo Decoder being used with a FD rack. Upon connecting a DMX line to the decoder the whole rig starts to pulse between about 20%and 40%. In the first instance I cured this by moving the DMX onto line B.

The next day the same problem occured on line B when the decoder was powered up with the DMX already attached. On this occasion the problem
was solved by changing to another DMX line from the desk.

We are running the show on a hog 2. Resetting the desk made no difference and the output was the same when the DMX line was changed over, so I have discounted the desk as a source of the problem.

Could it be the decoder prehaps a loose card, or is the multicore the culprit? any suggestions welcome.

I have the show running ok at the moment so this post is more for personnel intrest than a plea to get me out of the sh1t for the moment at least.

[niclights]

Have you tried speaking to service direct? That would be my first move.

[leofric]

Had this been a show stopper believe me I would have been on the phone. As I was I was in Denmark and the problem didn't come back, I was/am trying just to tap into the wealth of experience out here.

but cheers for your input Nic

Leo

[adamabcd]

I would try replacing the opto isolator ic's on the dmx input circuitry.
Believe it or not, they can get old and not work as well as when they were young. Alternatively, you can increase the input drive current by changing the 4K7 resisor to say 1K.