Dolby CP650 problem

[Neal Scanlan]

Hello,
I have a issue with my Dolby CP650 processor. The processor is set to boot to projector one on the front panel. From cold the processor boots correctly and P1 (red) is displayed however after a short while the display changes to P2 (amber). This happens without any inputs from the projector, it happens with the reader disconnected. Once this has happened if I soft or hard reboot the processor defaults to P2.

Can anyone suggest why this is happening?
Thank you

[Thomas Piccione]

Hello,
I have a issue with my Dolby CP650 processor. The processor is set to boot to projector one on the front panel. From cold the processor boots correctly and P1 (red) is displayed however after a short while the display changes to P2 (amber). This happens without any inputs from the projector, it happens with the reader disconnected. Once this has happened if I soft or hard reboot the processor defaults to P2.

Can anyone suggest why this is happening?
Thank you

What sort of setup are you running? Do you actually have 2 projectors and run in changeover, or 1 projector with a platter?

If you only have one projector connected the CP-650, it requires a jumper to be installed on the motor start connector on the back as described in the manual on page 24. I would check to make sure that jumper is there and hasn't fallen out or something similar.

[Neal Scanlan]

I use one projector and a platter.
The problem has only just happened, until now the processor has been working. I checked the jumper and it seems fine. Today I turned the processor on and off several times and it now defaults to projector 2 at start up. The display P2 is amber and I cannot get any response from the reader LEDs on the front panel!

[Marco Giustini]

What is the "reader LED on the front panel"? You mean the LCD screen and the buttons? Is the 650 frozen? If so, it could be the power supply. PSUs on the 650 are known for causing all sort of issues. If you have another one you can swap it. You can also measure the voltages at the test points which are behind the plastic front panel.

[Neal Scanlan]

Under the front cover are the 2 x LEDs that indicate the presence of an optical soundtrack signal, these are not lighting up in P2. The processor is working as it should in all respects except it defaults to P2 on start up or very soon afterwards.

[Jim Cassedy]

Whenever I've seen this problem, it's almost always been related to that little jumper that's supposed
to be installed on that 9pin connector on the back. I know you said you've checked it- - maybe check
it again. You're not seeing signal on the two LED's because the 650 ''thinks" its on projector two, and
you're feeding signal into the projector one inputs. (Can you try switching your proj to the Film-Tech Cinema Systems input on
the back?)
> I work with CP-650's a lot and I own two of them. I've personally never had a power supply issue
on any of the units I've got, except for the power switch itself failing. Maybe I've just been lucky, in
that regard, but if you have a meter, I'd check the voltages as someone else has suggested.
That being said, assuming there's not a major problem in the unit, the thing that's always worked
for me when a 650 starts acting wonky is to open it up and re-seat all the boards. There's only
a few of them-- and the hardest part is removing all the screws on the front panel to get to them.
But once you're inside, it's a piece of cake. But seriously- - check that little jumperthingy again.

[Peter Foyster]

Is there anything that can be done when the power switch becomes flaky?

Other than just not turning it off.

[Marco Giustini]

The power switch cuts 220V from the 650 and it automatically enters bypass mode.

its more a ‘bypass’ switch than a power switch. You can safely cut power to the 650, that switch does the same thing ?

that said check that the metal bracket holding the switch hasn’t bent inwards a bit. That would cause the switch to feel ‘flaky’ but it’s just because the actual switch is too recessed to be operated. You can easily bend it back outwards

[Neal Scanlan]

Hello Jim,
Thank you for your advice. I tried everything you suggested but unfortunately the problem persists. If I make the assumption that the issue is with the internal board is there a way that I can wire the 'Motor Start' plug permanently to P2, maybe using a jumper (like the one used for P1)

[Paul Finn]

Behind the front panel on the set-up panel is a DIP switch. Position 1 on that switch sets the wake-up (default) P1 or P2 on power up. With the CP650 OFF cycle that switch a few times ending up with the switch firmly in the P1 position. The only other things have been indicated above, especially the motor start connector plug on the back panel. Also as indicated, reseating the internal circuit boards, vacuuming the internal dust and cleaning the board edge connectors.

Note: NEVER connect/disconnect the SRD reader cable(s) on the back panel when the CP650 is powered ON!

Paul Finn