Cameras with a built-in motor drive need batteries with high power and capacity, because the motor drive needs much electric power to advance the film. The button cells used in many manual cameras do not provide sufficient electric power. The FS-1 therefore uses four AA batteries instead of button cells, the FT-1 uses four of the smaller AAA batteries in the standard configuration.
Remote Battery Pack AR for FS-1
Remote Battery Pack AR for FT-1
The power of batteries drops substantially in cold temperatures – this can even result in a non-operating camera due to battery failure when shooting outdoors in winter in cold environments. Konica provided a simple and elegant solotion to this problem: for both affected models, the FS-1 and the FT-1, so-called Remote Battery Packs do exist. Due to the different form and locations of the contacts on both camera models, the two Remote Battery Packs can only be used on the camera they were designed for, they are not interchangeable.
In place of the normal, camera-own battery compartment, a grip with respective shape and contacts is put on the camera body. This part provides the electrical contact to the camera body and a socket for a power cable. This cable leads to a external battery compartment, that takes four AA batteries for both FS-1 and FT-1 models. With the long cable, the external battery compartment can be put in a warm inner pocket – the batteries are kept warm and stay powerful. The power cable can be separated from the grip by a socket near the camera body, so that the camera can be stored away when not in use, without having to get out the external battery compartment.
Both Remote Battery Packs are offered infrequently and are not easy to obtain. It seems that this accessory is nothing interesting for collectors, because prices are moderate despite the parts being quite rare. If you often shoot in Winter in very low temperatures, you should consider to get a respective Remote Battery Pack for your body.
You can download a user's manual for the Remote Battery Pack AR for FS-1 on the accessories manual page. Operation of the Remote Battery Pack AR for FT-1 is identical, you can use the manual for this accessory as well.
AA battery compartment for FT-1
The AA batteries uses by standard in the FT-1 are very compact and also less heavy than the bigger AA batteries that are used in the FS-1. But on the other side, they are more expensive and have not as much capacity as the AA batteries.
A battery compartement for the use of AA batteries on the FT-1 was available from Konica as an accessory. It simply replaces the original standard battery compartment.
The AA battery compartment for the FT-1 is quite rare – perhaps because battery compartment contacts wear out or are damaged by leaking batteries. If one does show up, it is mostly quite expensive. In my opinion, it is not worth the high prices demanded, just to be able to use the bigger batteries, because the smaller AAA batteries still go a satisfying, long way in the FT-1 before they are empty.