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Topic: Distorted dolby tone waveform

Tony Bandiera Jr
Film God

Posts: 3067
From: Moreland Idaho
Registered: Apr 2004

posted 08-12-2009 09:58 PM

quote: Demetris Thoupis
I am not really aware of the CE readers but one thing to try is to tie the - signal of the dc power supply output to the chassis ground of your rack/projector as well as the ground of the power supply. most probably is a ground issue.

Not to pick on anyone, but: BAD advice! The CE readers use bipolar power supplies (for the reader electronics) and jumping the (-) side to ground WILL short out the supply! Which MAY damage the power supply but WILL LIKELY damage the reader's electronics.

Jumping the LED power to ground will accomplish nothing as it does not need a reference to ground.

Now the old JAX*LITE preamp module is a case where one side of the power input needed to be tied to chassis ground in most cases to avoid hum.

Eric: Is this a problem on a "new" install or is it something that cropped up on an existing install? It makes a difference in telling what the possible causes could be.

Listen to Sam's advice above..I think he's nailed it.

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Gordon McLeod
Film God

Posts: 9532
From: Toronto Ontario Canada
Registered: Jun 99

posted 08-12-2009 11:58 PM

Actually often connecting the led - to ground helps with some hum issues on many european machines
My suspicion is that the LED has ripple
Scope the DC to it and the Preamp ps as well

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Sam D. Chavez
Film God

Posts: 2153
From: Martinez, CA USA
Registered: Aug 2003

posted 08-13-2009 01:03 AM

The preamp can reject all sorts of power supply ripple, but the LED can not. As I advised, rule this out first.

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Chris Slycord
Film God

Posts: 2986
From: 청주시, 경북도, South Korea
Registered: Mar 2007

posted 08-13-2009 10:14 AM

quote: Jarret Chessell
Search "GIMP" on the internet. It's an open source photo editor incredibly similar to Photoshop. I recommend it to anyone concerned with piracy.

Although, "the gimp" is what I used to reduce the size of the pic, saying it is "incredibly similar to Photoshop" is an exaggeration at best. It's nowhere near as good, even if it is perfectly fine for everyday stuff average people would use it for.

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John Wilson
Film God

Posts: 5438
From: Sydney, Australia.
Registered: Dec 1999

posted 08-13-2009 07:26 PM

From the 'How to upload a picture' part of Film-Tech...

quote:
EASY INSTRUCTIONS FOR USING THE PROGRAM "PAINT" BUILT INTO EVERY WINDOWS OPERATING SYSTEM

Click START / PROGRAMS / ACCESSORIES / PAINT
From the PAINT program, click FILE / OPEN and select your image to be resized.

Click IMAGE / STRETCH-SKEW and reset the horizontal and vertical numbers equally from 100% and 100% to something like 15% and 15% (or if that produces too small of an image try 40% and 40%) and click OK.

I don't generally use that for my pics, but I have on occasions and it works just fine.

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Jarret Chessell
Master Film Handler

Posts: 288
From: London, Ontario, Canada
Registered: Jan 2009

posted 08-13-2009 10:27 PM

Alright, I'll admit Adobe Photoshop is superior to Gimp, however, you can't argue that it isn't feature packed, and mimics a lot of the functionality of photoshop. I was also pointing it out as a free alternative. Adobe products aren't cheap, and I don't endorse bootlegging (especially considering the field that most of us are in). When I first tried gimping I thought it was easy to use after Photoshop. Being able to work in layers and use many similar tools does make it fairly powerful for the average user.

Now how about that waveform?

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Randy Stankey
Film God

Posts: 6539
From: Erie, Pennsylvania
Registered: Jun 99

posted 08-14-2009 12:44 AM

Who said Mark was going to bootleg a copy of Photoshop?l

If mark has a copy of the program that he doesn't use he can give it to anybody he wants provided he erases it from any computer he has used it on.

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Tony Bandiera Jr
Film God

Posts: 3067
From: Moreland Idaho
Registered: Apr 2004

posted 08-16-2009 12:38 AM

Any chance we can get back on topic? [Roll Eyes]

Eric, have you tried any of the suggested fixes and if so, what happened?

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Eric Robinson
Jedi Master Film Handler

Posts: 538
From: Santa Rosa, CA
Registered: Jan 2005

posted 08-17-2009 06:32 PM

Thanks to all for the photo editing tips. The photo properties of my upload was not the issue. The issue is that I receive the following message after I submit the image:

"Your login has failed! Please check your username and password and try again. If you have forgotten your password, click here to have it emailed to you"

I have submitted this issue to the film-tech administrator and am awaiting any possible assistance.

Now back to the topic - - thanks for all of your inputs!
I found the problem to be the AC supply to the DC power supply which supplies power to the Component Engineering analog reader and LED simultaneously (2 outputs.)

The AC supply was being tapped off of two different outlets. The hot side was from one outlet on one circuit and the neutral was tapped off the neutral of another circuit. Why this is I have no idea. The hot side of the AC comes on when the automation triggers the electric dowser. I am using an entirely different AC power source now to power the DC power supply and everything works great. Something odd happened in the wiring of the projector but I'm not sure what it is. Additionally, I installed a new LED. And to top it off I had to install a new DC power supply module on the Ultra Stereo processor because it went up in smoke (figuratively.) All is well now. [Cool]

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Tim Reed
Better Projection Pays

Posts: 5246
From: Northampton, PA
Registered: Sep 1999

posted 08-20-2009 09:44 AM

quote: Eric Robinson
"Your login has failed! Please check your username and password and try again. If you have forgotten your password, click here to have it emailed to you"

Yes, you have to enter your user name and password before you hit the upload button... and it IS case-sensitive.

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