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Cameras, camcorders and decks can have all sorts of failures or intermittent problems with power connections and distribution of power within the unit. Trouble shooting in the field will often lead to a possible solution to get you through a shoot.

Is the unit totally dead? Check the unit's circuit breaker or removable fuse if you can find one. Fuses can fail at any time just from internal metal fatigue. It always helps to keep spares. Try another battery. If your batteries don’t work, try powering up through the 4 pin XLR input with an AC supply. Batteries have internal fuses or circuit breakers that can also fail.

We recently had a client who was battling an intermittent power problem when his camcorder died under battery power. He was able to power up the camera though the 4-pin cable and was able to finish the shoot with a battery to XLR power cord used for powering a color monitor with a camera battery.

Don’t always assume the camcorder is at fault. We have seen cases where batteries were so weak that cameras would not power up. The problem turned out to be a failed battery charger.

Another common problem has been the battery bracket to camcorder power lead attachment screws. Over time they can loosen and develop an intermittent connection. Remove outside screws that hold the bracket on, then tighten power lead screws.

The main power switch can wear-out and fail after years of service. If that is suspect, leave the switch on and power up and down by removing and installing the battery pack instead. This can hold you over until that switch can be replaced.

Loose internal circuit boards have also been known to cause power problems. If you feel comfortable, open the side of the camera opposite the deck and reseat the plug in boards. They are subject to poor connections because of vibration, shipping or whatever. We call this symptom, "connectoritis".

The camcorder may actually be working but only the display is out. Check the viewfinder image and video output to see if the camera is actually working or not. Viewfinders have also been known to fail and not show any picture at all. On some cameras, if the contrast control is turned down all the way, no picture will be visible, and it looks like the camera is dead. Check your output video on an external monitor. It’s not a bad idea to have one of those small LCD color monitors as part of your gear for back-up and camera color checking purposes.

While you are checking your output video for life, disconnect your lens and viewfinder cable. These on occasion, have been known to short out the camera’s power supply, preventing the camera from turning on. A good cameraman doesn’t need a viewfinder to shoot anyway. (tee-hee)

With over three decades of deck experience, I have seen several occasions where bad tape stock has caused overload of tape transport electronics. This overload can cause the transport power systems to go into a power protection shut down mode. There is no deck problem at all - it was just reacting to bad or damaged tape.

We have also seen with some cameras that have low voltage cut-off adjustment, for some reason fail and allow the unit to shutdown at a higher voltage of a good battery. This problem requires maintenance service to correct. It is often a condition where the menu driven adjustment changes by itself. Often we see problems like this happen if a battery is allowed to run dead. The internal microcomputer just gets stupid.

Shooting in wet conditions has also caused problems with power. Water droplets can easily short out sensitive electronic circuits and make the camera or deck inoperative. If you feel it could be moisture that has entered your gear, take a hair dryer to it and drive out the moisture. As long as saltwater has not entered your gear, you are probably ok. When salt water gets in, the water content may be driven out but the salt deposits stay. When just humid air hits the salt deposits, it absorbs the moisture and shorts out again. Here, professional help may be required to remove salt deposits and eliminate future problems.

Internal loose screws have also been known to work out of position and wedge themselves against an electronic circuit, causing a short. On one common dockable, this happens all too frequently. With the power unplugged from the unit, shake it and listen for something floating inside. If you hear something, open the side and try to shake it enough to remove it. This may allow you to power up and go on with shoot. Floating debris inside of electronic gear can cause expensive circuit board damage and should not be taken lightly.

As a follow up on our "Attack of the Killer Capacitors" article, we have had quite a few instances where old leaky or shorting capacitors have shorted out internal power supply outputs, making the camera inoperable. The camera, recorder, audio or any number of circuit failures can take your gear down. Often the problem begins with delayed power-up. Service will be needed soon.

Unfortunately, intermittent power problems are a pain to deal with. We dislike them because too often, gear comes in without any signs of the reported problem. We practically stand on our heads trying to recreate the problem. We subject them to the cold conditions of our refrigerator, heat them up under blankets, shake them, take them down back roads in a truck, and any number of other conditions. Of course, we have to charge for this service, but usually for only a fraction of the actual time spent. The biggest downside is usually with turn around time. You just cannot rush diagnosing intermittent problems.

Most of the time, the only way to diagnose is to start swapping boards, or whatever we suspect could be the problem. We once had a BVW-D600 with a bouncing black pedestal. We loaned out our BetacamSP camcorder for weeks while we tried swapping virtually every printed circuit board from CCD block, power supply, motherboard, and everything except the wiring harnesses. To complicate things, every time we disturbed the camcorder by swapping a board, or taking the camcorder on trips down that bumpy road, or just poking around inside, the problem would go away for the day.

After swapping nearly everything, the only parts left were the wiring harnesses, which had never been a problem in thousands of repairs. I swapped the suspect cable assembly to another deck and sure enough the problem followed. Now you know the rest of the story. Since then, we have repaired over twenty BVW-D600s with the same bouncing pedestal by just replacing the worn pins on those wiring harnesses. It’s a long story but it shows the complexity of some pesky intermittent problems.

We keep a database of every problem we encounter, and add the fixes to our preventive maintenance checklist for use on the gear that comes in. This way we can minimize future problems you may have in the field. For example, we inspect the internal boards for failure signs such as corroded or discolored capacitor leads. We find that most clients will go ahead with repairs if their gear is still making a profit. Please re-read this article on our website The Attack of The Killler Capacitor. I may be writing more on this subject soon.

As we all know "Stuff happens" but with a little maintenance education you may be able to get through an important shoot and save a client.

Take care,
Roger

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