Film-Tech Forum ARCHIVE: "Click" in Analogue Sound

This is topic "Click" in Analogue Sound in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

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Posted by Ian Bailey (Member # 1752) on 01-07-2007, 05:12 AM:

Just developed a "Click" in the analogue sound that appears to be only coming out of the centre speaker.
The "Click" does not happen in a uniform manner ie exactly every 2 seconds......the time between clicks seems to vary.
Can't seem to hear it in the booth monitor but can hear it in the auditorium.
Tried running a show in analogue and covering the red led.....sound stopped but "Click" was still there.
"Click" does not seem to be there running DTS.
Equipment:
JSX1000
Monee with Jax-Light.......it doesn't get any better than this!!!
Cheers Ian

Posted by Brad Miller (Member # 2) on 01-07-2007, 06:05 AM:

Disconnect the wires to the "solar cell" (jaxlite) from the JSX1000. Is the click still there? Also try stopping the motor and listen for it. I've had that sort of interference caused by the projector motor.

Posted by Ian Bailey (Member # 1752) on 01-07-2007, 07:50 AM:

Thanks for the information Brad.
I'm 3ookm's away from this problem so it will take a while
to try your suggestions.
Cheers Ian

Posted by Steve Guttag (Member # 268) on 01-07-2007, 08:13 AM:

Microswitches on platters are also noted for introducing clicks into the system.

Another source is the solar cell itself. During dry months, the plastic of the film will build up a charge and then discharge to the solar cell itself. Spacing the cell a little further away can also cure this problem at the expense of a little crosstalk.

Steve

Posted by Louis Bornwasser (Member # 3063) on 01-07-2007, 08:47 AM:

Might be a good time to "leverage" replacing the Jaxlight! The reduced output makes other problems larger. Louis

Posted by Ian Bailey (Member # 1752) on 01-07-2007, 10:20 PM:

Steve it's a Speco platter.....I don't think the clicking would be coming from that.The only adjustment I can see on the Jaxlight is the horizontal position of the light....can't see how the solar cell's(receiver) position can be changed!
Lois I'm not a big fan of Jaxlights.......would love to replace it......it all comes down to money!!
Cheers Ian

Posted by Gordon McLeod (Member # 33) on 01-08-2007, 08:19 AM:

The grounding of the jax light often is the source of them being noisy you may have to try some creative grounding techniques
It also could be getting into the mains of the preamp for the jax light

Posted by Ian Bailey (Member # 1752) on 01-10-2007, 08:18 PM:

Hi Guys
Just thought I'd let you know the result to this problem.
The "clicking" was actually coming from the Format card in the JSX1000.This card has been giving me intermittent problems for a while......Digital i/p dropping out(intm.).....then External i/p dropping out......then analogue i/p dropping out(intm.)........then the clicking noise in the centre channel which was a permanent problem.
I installed another Format card with the latest REV. level and all seems good at the moment.
Cheers Ian