Film-Tech Forum ARCHIVE: circuit diagram for changeover p1 and p2

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Posted by Victor Garcia (Member # 7158) on 02-01-2013, 07:46 PM:

Has anyone a Circuit Drawing for the changeover p1 and p2 for CP650?

Posted by Christos Mitsakis (Member # 143) on 02-03-2013, 11:04 AM:

Hi Victor,
have you checked the manual in the warehouse (page 24),
Or are you seeking something else?

C.

Posted by Bernie Anderson Jr (Member # 410) on 02-03-2013, 02:28 PM:

There is a contact closure for projector 1 and 2 for analog. The schematic is in the manual. You can use a latch relay to hold projector 2.

For digital, you would need motor relays to tell the 650 that another projector is about to come on screen. This is totally separate for the analog wiring.

Bernie

Posted by Scott Norwood (Member # 30) on 02-03-2013, 02:48 PM:

With the CP650, you can just use momentary contacts to select either projector 1 or projector 2. This can be as simple as pushbuttons next to each machine. No relay needed.

Alternatively, a held contact can be used to select projector 2, as with previous Dolby processors, but for some reason people here have recommended against that.

The only disadvantage that I am aware of to the momentary-contact method is that, at powerup, the CP650 will always have either projector 1 or projector 2 selected (this is configurable with the DIP switches under the front-panel door). This may or may not be in sync with the picture changeover position. You may or may not care about this.

And, yes, the motor-start relays are for SRD only.

Posted by Louis Bornwasser (Member # 3063) on 02-03-2013, 09:35 PM:

The motor start relays are not optional for digital.

On the CP-500: maintained analogue contact will not always work. If you end up on #2, powering down and powering up on the 500 will result in no sound. Pulse to #1 and then back to #2 and you will have sound. Note I do not know if this is so for the 650 as well. Louis

Posted by Victor Garcia (Member # 7158) on 02-04-2013, 07:43 PM:

thanks friends!!