I think it's the later. Here's why: our automation (RGM) requires an outboard cue to end the show. It must be a pulse. Well, in this house the tail always shows on screen. The show doesn't end. If an outboard cue is always present, there would be no pulse, so the automation would not close the dowser and end the show.

So, my first thought was the cue sensor module was bad. I proceeded to swap it out, but when I removed it, the outboard LED was sitll lit! At this point, my guess is there is something wrong with the circuit board on the FM-35. I removed the cover to visually inspect the board, but I couldn't find anything wrong. Any ideas what the problem could be?

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What and where are the other boards on the unit?

Sure, I can call CE for advice, but Darryl's suggestion was to order a replacement from them, and I can't do that.

Aaron

So why would those traces being cut in half cause a constant outboard cue?

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There is a long, skinny PC board along the back of the unit that can be seen from the operator's side of the machine. If you have a film path misalignment the film will rub against that board and eventually saw a line into it, cutting one or more of the traces. It will cause irratic behavior and eventually one of the cues will come on permanently.

You can disassemble the unit and remove the PC board. Take some fine-grade emory cloth and remove the green colored layer of protective lacquer from the surface of the board. Just expose the parts that have damaged traces. Don't sand the whole board! If you look closely, you'll be able to see where the traces have been cut. Take some alcohol on a Q-Tip and clean the bare metal of the traces. Take your soldering iron and apply a thin coating of melted solder to the bare metal. You're not trying to bridge the gap yet. You are just "tinning" the bare metal. It makes it easier to solder to in the next steps and it makes for a better, more secure connection.

At this point, I should mention that you only need to apply enough heat to liquify the solder. Once it starts to flow, you only have a few seconds before you start doing heat damage to the traces on the board and any electronic components that may be in the area. If you see the copper foil start to peel away from the board you are doing damage and you should stop what you are doing.

Once the traces have been tinned, you can get a piece of thin guage stranded wire and strip it clean so you can access the strands inside. Cut off enough pieces of these hair thin wires to bridge any gaps in the traces. They don't have to be very long. Just enough to bridge the gap and leave about 1/8 of an inch on either side of the gap. A 1/4 to 1/2 inch piece should do the trick. If the trace is curved or goes around a bend, form the piece of wire to match the shape of the trace. You do NOT want the piece of wire to touch anything else but the place you are trying to repair.
Use a pair of tweezers and a magnifying glass if you have to. The more accurately you work the better off you are gong to be.

Lay the wire in place over the gap and carefully apply heat. Touch the end of your piece of solder to the place where the tip of the iron and the wire meet and melt a SMALL blob of solder in place. Use the tip of the iron to smooth the solder so it covers the wire. Make SURE the liquid solder doesn't "leak" onto neighboring areas of the board. If you cleaned and tinned the areas in question properly, the solder will seem to flow right down the length of the wire and cover the gap, almost as if by magic.

Once you are satisfied with your work, let the whole thing cool for a few minutes. Use a pair of small wire cutters (or toenail clippers) to trim off any excess wire. Take some Xe-Kote and a toothbrush and clean the areas you just soldered. You must remove all of the flux from around the joints you just made. (Some kinds of soldering flux are conductive.) Clean the area again with alcohol to remove any Xe-Kote residue. Once the area is absolutely clean reassemble the unit and test it. If you are satisfied with your handywork, take some nail polish and cover all the areas that you sanded bare. (If you happen to be able to get your hands on some clear, green PC board lacquer, all the better but nail polish will do fine.) Before you put the unit back into service, it might be a good idea to take some electrical tape and cover that whole area of the PC board to help protect it from the same kind of damage in the future. Just about the only criticism I have about the FM-35 is that there should be a cover over this area of the PC to protect it from this kind of damage. Admittedly, this is a small criticism.

To finish up the job, realign the falesafe to make sure the film stays inside the intended film path through the unit. If it's touching against any other part of the unit, except for the rollers, you are either going to damage the unit or the film itself.
While you are at it you might as well go around and check any other units you have for this kind of mishap. You already have all the tools out, right?! Why not kill two birds with one stone?

Oh, yeah! Maybe I should mention that if you've never used a soldering iron before, you should leave the job to somebody who has... Your engineer, for example! (At least give your engineer a call or send him an e-mail first!)

Lastly, you can have the powers-that-be in your company order you a whole, new unit. Then you can send the old one back once you have the new one working. If you do that, the company should only charge you for the cost of the parts needed to repair the unit (plus labor). Even if you get a little bit of money back, it'll still be less expensive than buying a whole new one. (Which is what you WILL have to do if you try to repair the old one and mess it up!)

Just remember the old saying that my Step-Dad always tells me: "Measure twice. Cut once."

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Don't try to jumper the connections by hand while the power is on to the unit! If it wasn't busted before you tried that, it just might end up busted after!
Just take a flashlight and get down on your hands and knees under the projector. Look really closely, in good light and the "saw marks" should be pretty plain to see. Although 3 or 4 of us guys concur with the same diagnosis, that's still not a 100% sure thing! Make sure you can find the problem we describe before you go messing around. (No, I'm not treating you like you are stupid... it's just a CYA thing on my part! ;0 )

No diagrams are available in any of the documentation I have. Actually, there's nothing to the thing if you look at it. It's a pretty well-designed piece of equipment and it's put together pretty "tight" as well. A reasonably intelligent person ought to be able to figure it out.