Film-Tech Cinema Systems
Film-Tech Forum


Post New Topic  Post A Reply
my profile | my password | register | search | faq & rules | forum home
  next oldest topic   next newest topic
» Film-Tech Forum   » Operations   » Film Handlers' Forum   » Manual/Schematics for Dolby SA2 Surround Adaptor

   
Author Topic: Manual/Schematics for Dolby SA2 Surround Adaptor
Robert W. Jones
Film Handler

Posts: 74
From: San Antonio, TX
Registered: Mar 2007


 - posted 10-08-2007 01:06 PM      Profile for Robert W. Jones   Email Robert W. Jones   Send New Private Message       Edit/Delete Post 
Hello all,

Looking for a manual for the SA2.

If you can help me out please contact me. Need if for my screening room equipment.

thanks,

Rob

 |  IP: Logged

Bill Gabel
Film God

Posts: 3873
From: Technicolor / Postworks NY, USA
Registered: Jan 2002


 - posted 10-08-2007 01:41 PM      Profile for Bill Gabel   Email Bill Gabel   Send New Private Message       Edit/Delete Post 
Look over in the manual section, there is info under the Dolby CP-100 install manual about the SA 2 Surround Adaptor.

 |  IP: Logged

Robert W. Jones
Film Handler

Posts: 74
From: San Antonio, TX
Registered: Mar 2007


 - posted 10-08-2007 02:13 PM      Profile for Robert W. Jones   Email Robert W. Jones   Send New Private Message       Edit/Delete Post 
Bill,

Thanks. Actually the SA2 is going on a CP100 in my screening room. What I would like to have if anyone has access to a copy is the schematics for the unit with a 116A card. The reason is I can do any repairs as need, and the schematic or service manual will provide the values and test points.

Thanks for your help. Forgot about the section in the CP-100 manual for connection diagrams and setup.

Rob

 |  IP: Logged

Mark Gulbrandsen
Resident Trollmaster

Posts: 16273
From: Bountiful, Utah
Registered: Jun 99


 - posted 10-08-2007 02:51 PM      Profile for Mark Gulbrandsen   Email Mark Gulbrandsen   Send New Private Message       Edit/Delete Post 
Exactly what is the problem or are you trying to figure out if its in the mainframe or the 116 card?

BTW: CAT 116 cards are really unacceptable for SR playback so you might want to nix the whole thing and just build in a late model CAT 150 card right into the CP-100. There's plenty of room in there and I've done this to quite a few of them. The later decoders are unbelievably superior.... the 116 is a dinosaur. The optical preamps can also be modified for proper slit loss compensation characteristics for narrow slit lens or reverse scammers.

Mark

 |  IP: Logged

Marin Zorica
Jedi Master Film Handler

Posts: 660
From: Biograd na Moru, Croatia
Registered: May 2003


 - posted 10-08-2007 04:49 PM      Profile for Marin Zorica   Email Marin Zorica   Send New Private Message       Edit/Delete Post 
quote: Mark Gulbrandsen
The optical preamps can also be modified for proper slit loss compensation characteristics for narrow slit lens or reverse scammers.
Can you tell me how to modify Cat 108?

Because with 108 on CP50 I've reaching 12,5KHz flat with HF correction, and no isn't problem in sound head because with mine own designed preamplifier I reach 16KHz flat!!!!

 |  IP: Logged

Robert W. Jones
Film Handler

Posts: 74
From: San Antonio, TX
Registered: Mar 2007


 - posted 10-08-2007 06:14 PM      Profile for Robert W. Jones   Email Robert W. Jones   Send New Private Message       Edit/Delete Post 
Mark,

Good info, thanks! Not trying to diagnose a problem. Just looking for a set of schematics for future reference. Guess I'm a geek, but track down schematics for everything I have. Makes it easier to find a bad electolytic cap (which fail often in time), or a handy test point value.

I do have pleanty of room in the CP100, as I'm not running 70mm.

Rob

 |  IP: Logged

Mark Gulbrandsen
Resident Trollmaster

Posts: 16273
From: Bountiful, Utah
Registered: Jun 99


 - posted 10-08-2007 08:00 PM      Profile for Mark Gulbrandsen   Email Mark Gulbrandsen   Send New Private Message       Edit/Delete Post 
Actually I would reccomend re-working the power supply in it... replace alll the electrolytics. Although the CP-100 power supply is one of Dolby's best designed power supplys the sheer age of the caps justifies rebuilding it.

You can find the 116 schematics in the Dolby CP-50 manual here on Film Tech... the 50 used it in its early years along with I think a 146 front decoder card. There is a big problem though and that is finding the delay I.C.'s... they are VERY obsolete and were also used in the early CAT 150's. If you look around for a 150 card stick to one of the later ones.

Mark

 |  IP: Logged

Louis Bornwasser
Film God

Posts: 4435
From: prospect ky usa
Registered: Mar 2005


 - posted 10-08-2007 08:38 PM      Profile for Louis Bornwasser   Author's Homepage   Email Louis Bornwasser   Send New Private Message       Edit/Delete Post 
I believe the old cp-50 front decode was a cat 110, with the 116a in the surround slot. Louis

 |  IP: Logged

System Notices
Forum Watchdog / Soup Nazi

Posts: 215

Registered: Apr 2004


 - posted 12-14-2008 01:20 PM      Profile for System Notices         Edit/Delete Post 

It has been 432 days since the last post.


 |  IP: Logged

Stephen Furley
Film God

Posts: 3059
From: Coulsdon, Croydon, England
Registered: May 2002


 - posted 12-14-2008 01:20 PM      Profile for Stephen Furley   Email Stephen Furley   Send New Private Message       Edit/Delete Post 
I'm still somewhat confused about this. The CP-50 manual says:

"Note: Early CP-50's used a Cat. No. 110 (or Cat. No.82) in slot 6 to provide left, center, right decoding. Slot 7 contained a link card (Cat. No. 115) for non-surround installations, and a surround decoder (Cat. No. 116A) for installations with surround. This arrangement was superseded in April, 1979 by the Cat. No. 110L/150 system."

What was the difference between the Cat. 110 and 82? I'd never heard of the 82 before, but it seems to be the Mono/Stereo Optical Module used in the CP-100.

It seems that Dolby Stereo progressed quite quickly in its first few years. As far as I can make out, with the CP-100 there were five generations:

1. Three channel, without surround, using internal modules.

2. Surround channel by the addition the Cat. 92 Pentoptical module and an early model SA-2 containing a Cat. 116 surround decoder and a separate delay module, with the front channels still being handled by the modules in the CP itself.

3. As above, but using a Cat. 116a decoder, which included the delay on a daughter board. Later SA-2 units did not include the separate delay module, and therefore could not use the original Cat. 116. They also did not require mains power, as the earlier units did.

4. The SA-3 did not change the decoding, but introduced internal switching for optical/magnetic surround, in place of the external relay unit.

5. SA-4 introduced, using the Cat. 150 to decode all four channels.

Have I got that about right?

What was the Cat. 94 Pentoptical Module which had to be installed in the CP-100 when used with the SA-2 and 3. If a Cat. 82 and 116a between them could decode all four channels in an early CP-50, why was this extra card needed in the CP-100?

Life really does seem to have become much less complicated with the introduction of the new cardset for the CP-55, and the use of the Cat. 150 for everything.

What were the differences between the various generations of Cat. 150?

 |  IP: Logged

Louis Bornwasser
Film God

Posts: 4435
From: prospect ky usa
Registered: Mar 2005


 - posted 12-14-2008 02:22 PM      Profile for Louis Bornwasser   Author's Homepage   Email Louis Bornwasser   Send New Private Message       Edit/Delete Post 
The SA-2 had the 116 in it with a permanently mounted delay system. The 110 was kept in the cp-50. The Sa-2 was an option.

The pentoptical module was a somewhat successful 5.0 attempt. Probably deemed too noisy on the surrounds. Combining the two channels helped a little bit on the noise problem. (Look at the drawing for early CP-50, you can see the l&r surrounds tied together.)

Really great stuff for its day; not too shabby now with SR and 150 card!

Early Dolby did not support surround since "the reality is on the screen." Louis

 |  IP: Logged

Sam D. Chavez
Film God

Posts: 2092
From: Martinez, CA USA
Registered: Aug 2003


 - posted 12-14-2008 02:48 PM      Profile for Sam D. Chavez   Author's Homepage     Send New Private Message       Edit/Delete Post 
"What was the Cat. 94 Pentoptical Module which had to be installed in the CP-100 when used with the SA-2 and 3. If a Cat. 82 and 116a between them could decode all four channels in an early CP-50, why was this extra card needed in the CP-100?"

There were 3 format slots in the 100 occupied by various cards over the years. I believe the Cat. No. 82 LCR card had no way of returning the audio signal from the SA2 or SA3 surround adaptor, so the Pentoptical(sp) module was needed for this purpose. This module also decoded the LCR in a slightly different way than the 82 so one could switch from the format with the 82 and the 94 and the front channel separation was slightly different.

Steve will be a long any minute now to correct me on all this.

Speaking of the 100, there was the Cat. 135 that superceded the 84 to provide 10db more gain from the MPU, and the 148 card to interface with the SA4 and the 148B to interface with the SA5 and this is a topic all to itself.

 |  IP: Logged

Steve Guttag
We forgot the crackers Gromit!!!

Posts: 12299
From: Annapolis, MD
Registered: Dec 1999


 - posted 12-14-2008 02:57 PM      Profile for Steve Guttag   Email Steve Guttag   Send New Private Message       Edit/Delete Post 
Nope, the CP100 history pre-dates me a bit. I've had my hands on them, tuned a few but mostly observed its history from afar.

The Cat 110/82 thing though...they were the same card, I'm pretty sure with the metal frame being the difference (it was in a metal frame for the CP100 for use in a format slot).

Sam did fail to mention the Cat 148SR for use with the SRA-5...I bring it up here just for completeness.

Steve

 |  IP: Logged

Gordon McLeod
Film God

Posts: 9470
From: Toronto Ontario Canada
Registered: Jun 99


 - posted 12-14-2008 08:41 PM      Profile for Gordon McLeod   Email Gordon McLeod   Send New Private Message       Edit/Delete Post 
the cat 82 and the 110 were the same they decoded LCR with a gain riding circuit of 3 db this was passed on to the surround decder that was outboard in the SA2

 |  IP: Logged



All times are Central (GMT -6:00)  
Post New Topic  Post A Reply Close Topic    Move Topic    Delete Topic    next oldest topic   next newest topic
 - Printer-friendly view of this topic
Hop To:



Powered by Infopop Corporation
UBB.classicTM 6.3.1.2

The Film-Tech Forums are designed for various members related to the cinema industry to express their opinions, viewpoints and testimonials on various products, services and events based upon speculation, personal knowledge and factual information through use, therefore all views represented here allow no liability upon the publishers of this web site and the owners of said views assume no liability for any ill will resulting from these postings. The posts made here are for educational as well as entertainment purposes and as such anyone viewing this portion of the website must accept these views as statements of the author of that opinion and agrees to release the authors from any and all liability.

© 1999-2018 Film-Tech Cinema Systems, LLC. All rights reserved.