Avolites Pearl Expert problem

[lxhipster]

Hi guys,

 

A friend of mine who is currently doing a show in Paris is having a problem

with his Pearl Expert. He claims that there has been an interference issue

with Walkie Talkie signals which causes the DMX output from the console

to shake causing the lights to flicker.

 

He also claimed that other people is having issues like this with their

console as well and that he is looking for another console to work with, so

I would like to ask whether is anyone having the same problem with

RF disturbing the DMX signals?

 

He said that he tried changing the DMX cables, used Wireless DMX,

put splitters & boosters and nothing worked. This issue only happens

when a Walkie Talkie is placed near the console and if there is no

walkie talkie within a 5m vicinity of the console, then it does work fine.

 

I was actually wondering whether is it a Production-wide issue or

is it only a glitch with that specific console.

 

Cheers!

 

 

Poon

[Ali2580]

I'd be quite interested to know this too actually as I am investing in new two way radio's for the theatre I do lighting and sound at and I don't want to put the radio near the lighting desk during a show if this is true for all DMX. :blink:

[tom_the_LD]

Which walkie talkies are they? Thinking aloud, perhaps if they are cheap ones this could be the issue? All the techs at our theatre have walkie talkie radios on and experience no problems - admitedly the in house desk is an ETC but there have been Pearl experts bought in during previous shows.

[lxhipster]

Hi!

 

I just ringed my friend and he said its one of the Motorolas.

I've never had this problem with any other Lighting Consoles which

includes the Avo Pearl 2008/2010, Avo Pearl Tiger, Compulite,

Hog, Frog, Grand MA or Maxxyz.

 

BR,

 

Poon

[Tomo]

If you put an actively transmitting walkie-talkie on top of almost any lighting console (or PC, or most modern electronics) it will behave oddly.

It's the same with mobile phones.

The radiated power density when the antenna is that close is simply too much for the electronics to shake off.

 

There was also a video on YouTube somewhere of a guy flipping RCD breakers simply by waving a walkie-talkie radio near them.

 

That said, 1m separation should be more than enough. I've never heard of a lighting console being affected by a radio handset further away than an inch or two.

 

Has he tried putting the radios close to a sound console?

[JBToby]

Sorry to hear you are having problems

 

Some radios are very powerful (read illegal) and can affect the faders of the console, this can in curtain cases affect the DMX levels

However as you state that it happens even at more then one meter I suspect there is another issue at play.

To me this looks like the DMX cables are picking up the radio and possibly inducing it into the Expert.

We have published an ECN mid last year about this issue. http://www.avolites.org.uk/support/ecns/ECN-0184fax.pdf

Two bits of wire (keep them short please) will likely sort this out

 

We have tested the Pearl Expert with legal radios besides the console without negative effect. Some radios can affect the faders when the radio is placed on top of the console and operated (Tx).

Some very high power radios can negatively affect the console if the antenna is pointed directly at the PC I/O connectors

 

JB

[niclights]

Avo specifically advise not to place such devices on the console for this reason.

 

/edit: JB beat me to it. I don't think OP actually said it was more than 1m?