Powering the Revolution Bolex with AA batteries The Revolution Bolex is very energy-efficient and a 12-cell battery pack using standard AA alkaline cells can power it for over a thousand of feet of film. Current draw at 24fps with a full load of film and a 12-cell supply is about 350mA. An alkaline AA battery has a capacity of about 2,500mAh. Since we'll replace them when they've dropped to 1.25V, assume we're only going to use their first 1,000mAh of capacity. At a 400mA draw, that's 2.5 hours of running. 1,000 feet of 16mm film will take 28 minutes to shoot. So if we get 2.5 hours running time, that's 50 rolls of 100' loads on one set of batteries! Taking into account that we'll be starting and stopping the camera repeatedly, a more realistic estimate would be 20-25 rolls of film. At 99-cents for a four-pack, battery cost will be a tiny cost of filmstock and processing. And we never have to worry about recharging! Making a 12-cell AA Battery Pack We'll need some battery holders. The one in back is an 8-cell holder with a battery snap connection. On the right is a 4-cell holder that also has a handy on-off switch. We'll need one battery snap and shown here is a 2-pin Molex connector that will match the standard NCS XLR-cable. Solder the black wire of the 9V snap to the red wire of the battery case. To keep things neat, you can unsolder the red wire going into the battery pack and solder the black wire direct. The red wire from the snap and the black wire from the battery case get soldered to the XLR connector. A thicker wire is used for strength. Here it is all completed. Just need to gaffer tape the two packs together. Under a pound total weight! Ready to shoot! All the parts described here can be purchased from jameco.com. A 12-cell pack is good for filming up to about 32-36 fps. If you want to be able to shoot at the fastest speeds you can use two 8-AA holders.
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