The AKG ASU 4000 is an in-line power supply unit for use in large antenna networks to feed 12 V DC into an antenna line. With the help of the ASU 4000, all connected AKG antenna network components such as the AB 4000, SRA 1 and RA 4000B can be remotely powered even if there is no power coming from the connected PS4000 multi-coupler (e.g. in distributed antenna networks using standard antenna combiners). The ASU 4000 is equipped with 2 BNC connectors, 1 power indicator LED as well as a DC input for connection of the AC/120/500 adapter. The ASU 4000 is built into a waterproof metal housing and therefore is suitable for outdoor use. The ASU 4000 can power up to 3 active antenna components (e.g. AB 4000, RA 4000B, SRA 2).