15RailKing NW-2 Operating ManualRAILKINGSELF-RECHARGING BATTERY BACKUP SYSTEMProtoSounds® state-of-the-art design includes a self-recharging batterybackup system for improved performance at any speed. The self-rechargingbattery backup system is automatically turned on or off whenever trackpower is turned on or off. There are no switches to turn on or off to enjoythe benefits of the automatic battery backup system. The battery ensuresthat power to the sound system will remain on during directional changes,setting RESET options, or when traveling over dirty track and switches.The battery is a rechargeable NiCad type which is continually chargedfrom the track when power is applied. NiCad batteries are a dry battery andshould not leak or cause any damage to your locomotive and will last up tofive years or longer. If you notice that the sounds seem distorted or garbledat low voltages or become silent when power from the transformer is shutoff, the battery may be going bad. Before replacing the battery, you shouldput the engine in NEUTRAL and leave the transformer throttle at about 12volts for fifteen minutes. This should temporarily recharge the battery. Ifthe garbled or distorted sounds are reduced, then your battery charge hasworn down. You can give your battery a full charge by leaving the engineON in NEUTRAL for 16 to 18 hours.REPLACING THE PROTOSOUND® BATTERYIf you notice that the sounds seem distorted or garbled at low voltages orbecome silent when power from the transformer is shut off, the battery maybe going bad. Before replacing the battery, you should put the engine inNEUTRAL and leave the transformer throttle set at about 12 volts for 15minutes. This should temporarily recharge the battery. If the garbled ordistorted sounds are reduced, then your battery charge has worn down. Youcan give your battery a full charge by leaving the engine ON in theNEUTRAL position for 18 hours. (Make sure the smoke unit switch is inthe OFF position to prevent harm to the smoke unit wicking).If you need to replace the battery, replacement ProtoSound® batteries areavailable from MTH ProtoSound® Electronics at 7020 Columbia GatewayDrive, Columbia, MD 21046. A standard 9v alkaline battery can besubstituted as a temporary fix, but since alkaline batteries can’t take acharge, it will eventually wear down. Regardless, it should give you a weekto a couple of months use while you wait for your replacementProtoSound® battery to arrive.