Kathrein ESU 57 loop-through socket (21110029)

The ESU 57 is a loop-through outlet engineered for single-cable and multi-switch satellite distribution systems, delivering TV, radio, and SAT signals through a single wall plate. Its 10.5 dB tap loss balances signal levels across cascaded outlets, while the 1.5 dB through loss preserves signal integrity for downstream devices.

Highlights

• Three outputs: IEC male for TV, IEC female for radio, and F-connector for SAT
• Wide frequency coverage: 109–862 MHz (TV), 87.5–108 MHz (radio), 950–2200 MHz (SAT)
• DC pass-through up to 500 mA for remote powering of LNBs or multiswitches
• Return path capable (5–68 MHz) for interactive services
• High shielding factor (>75 dB) minimizes interference

In daily use

The ESU 57 installs flush-mounted in standard wall boxes, providing a clean, professional finish. Its loop-through design allows multiple outlets to be connected in series without significant signal degradation, making it ideal for residential and commercial distribution. The DC pass-through simplifies powering of active components, reducing cabling complexity.

Full specifications

• Socket type: Loop-through (Durchgangsdose)
• Application: Single-cable systems (JESS/JESSX), multi-switch systems
• TV output connector: IEC male
• Radio output connector: IEC female
• SAT output connector: F-connector
• Frequency range TV (forward): 109–862 MHz
• Frequency range TV (return): 5–68 MHz
• Frequency range radio: 87.5–108 MHz
• Frequency range SAT: 950–2200 MHz
• Tap loss TV/radio: 10.5 dB
• Tap loss SAT: 10.5 dB
• Through loss TV/radio: 1.5 dB
• Through loss SAT: 1.5 dB
• Impedance: 75 Ohm
• Shielding factor: >75 dB
• DC passage (SAT): Yes (max. 500 mA)
• Mounting type: Flush-mounted
• Return path capability: Yes
• Compatibility: DVB-T/T2, DVB-C, DVB-S/S2

Final note

The ESU 57 combines reliable signal distribution with low insertion loss, ensuring consistent performance in complex satellite installations.