I have a D-40 Moultrie, that I would like to hook up a 6 or 12 volt recharable battery to. The instructionsshow a connection for an external battery, but no cable is listed as an accessory. Does anyone know how to do this? By the way, I had to send the first one back to Moultrie for a bad flash and now this one seems slow to work and difficult to turn on for set up.