Film-Tech Forum ARCHIVE: Dolby CAT85C

This is topic Dolby CAT85C in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

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Posted by V.V.Tushit Vijay (Member # 5455) on 11-22-2010, 09:47 AM:

I seen the parts list in Dolby CP50 manual for DOLBY cat85c . ANy one had the Schematics for DOLBY CAT85C. I am eager to get ready it any one had the PCB layout of the card.

Regards,
V.V.Tusith

Posted by Gordon McLeod (Member # 33) on 11-22-2010, 04:30 PM:

the schematic used to be in the CP50 CP100 and cp200 manual

Posted by V.V.Tushit Vijay (Member # 5455) on 11-22-2010, 06:21 PM:

Thanks Sir. But some of the values were there . they are not given in schematics. they had given it as STD FET, STD PNP, STD NPN. Can you get me the values for that . and the layout given is Component side. How about the solder side of it.

regards,
V.V.Tusith

Posted by Tony Bandiera Jr (Member # 2365) on 11-22-2010, 08:57 PM:

VV, your best bet is to seek out an assembled CAT 85c. Why?

First off, the "solder side" (or foil pattern for etching) has never been published/released by Dolby.

Second, you'll notice some components labeled "AOT" which means that the actual value of that part is determined by testing and calibration.

The time, money and small probability of success in getting a working, properly calibrated CAT85 makes this a very bad idea as a "build it yourself."

The Component Engineering SG-1 LINK is still available and works very well.

Posted by V.V.Tushit Vijay (Member # 5455) on 11-23-2010, 12:45 AM:

Thanks for your Suggestion but here i had only 5 Processor. And In India they wont pay correct amount for the tech support. So i am planning to do these things in a smaller way. To Serve them better . And make the audio perfect in the theater.

V.V

Posted by Gordon McLeod (Member # 33) on 11-23-2010, 01:31 AM:

I guess there are several issues
one is if one wants to be in an industry then there is a cost of tools involved
The schematic is more or less complete since even making a noisy transistor PN generator many of the components will be field matched
Also one does not need a 85c any noise generator that one can calibrate to the correct level for the processor in question and a simple extender /pinpoint insertion card will do