Inside the 100‑Hour Island Live Stream: Technical Deep Dive of the Tim Broadcast System

Overview

On August 15, 2025, the Tim system completed a continuous 100‑hour island‑survival live broadcast, dividing the technical solution into five subsystems: video, audio, network, control, and synchronization.

Video System

More than 20 cameras were deployed, including PTZ SONY ILME‑FR7, fixed‑point ZCAM E2‑S6, security‑grade dome PTZ cameras and ultra‑long‑range PTZ units. These cameras were chosen for high reliability, climate tolerance and infrared night‑vision capability.

Transmission

FR7 and ZCAM video signals were aggregated via optical modules and optical transceivers back to a production cabin, while monitoring cameras streamed via RTSP to a decode server and were converted to SDI baseband. Monitoring streams exhibited variable latency due to codec buffering; the team omitted the alignment step to avoid the high cost of synchronising these feeds.

Interview & B‑Roll Capture

Interviews and on‑the‑fly shots used SONY HDC‑5500 and the newly released PXW‑Z380 handheld camcorder, which offers superior autofocus, automatic subject detection and composition. The cameras were linked to a CBK‑RPU7 remote‑production unit and an NXL‑ME80 media‑edge gateway, enabling sub‑2‑frame latency 4K video back‑haul over 5G, with support for signal return, RCP reverse‑control and HEVC encoding with QoS.

Video Production

Switching was performed with a Blackmagic Design ATEM 4M/E Constellation 4K cascaded to an ATEM Constellation 8K. The lead operator used the ATEM 4M/E for primary cuts and an Elgato Stream Deck Studio as an AUX panel to assign four sub‑windows. Program output passed through a Teranex AV for audio embedding and AV‑sync correction, then to two ATEME Titan Live encoders in hot‑standby, streaming to Bilibili and Douyin.

Video Capture

Fourteen Blackmagic HyperDeck Studio 4K Pro units and two NAS servers formed the recording backbone. HyperDecks wrote directly to SMB shares over 10 GbE, avoiding interruptions during long‑duration recordings. FR7 timecode was aligned via a frame‑sync device. ZCAM’s API allowed remote HTTP GET download of footage; a custom script uploaded segments to NAS, monitored card usage and automatically deleted files after successful backup, enabling uninterrupted circular recording.

Audio System

The Shure Axient Digital series was selected, using an ADX1 ultra‑portable transmitter and an AD4Q four‑channel rack receiver. One receiver was placed in the shore cabin and another in the island cabinet, each with directional antennas and a four‑element diversity setup to eliminate blind spots and mitigate rain or dew effects.

Commentary

Commentary was handled by a Merging Anubis SPS running the Commentary Mission add‑on, providing four‑channel dynamic EQ and compression, programmable program, sidetone and talk‑back levels, and rapid mute for unexpected sounds. The unit supports ST2022‑7 seamless failover, PoE + DC dual power, and remote parameter adjustment via a web interface.

Mixing

Audio mixing employed a Yamaha DM7 with 120 input channels and a 144×144 Dante interface, allowing direct video‑system audio feed capture. Qlab drove up to 48 tracks of ambient sound and music. Plugins supplied dynamic EQ, multiband compression and limiting (Portico 5043). Tally signals from the video switch triggered automatic fader starts for corresponding microphones. The N‑1 bus facilitated IFB and program routing, reducing hand‑off time and risk.

Monitoring

Genelec 8341 coaxial active monitors, paired with the GLMv5 calibration suite, generated a GRADE report to identify and correct room acoustic defects. A Genelec 9320 controller provided AES/EBU digital monitoring.

Audio Capture

Sound Devices Scorpio multichannel recorders and a Mac Studio running Reaper (with a LAWO VSC virtual sound card) captured multi‑track audio. The system ingested Dante streams and AES67 multicast audio, recording directly to the Mac.

Network Infrastructure

Core switching used Huawei CE6855‑48XS8CQ models with PTP support; all devices connected via 10 GbE fiber. VLANs segmented management and media traffic. Two redundant servers (one on‑site, one at the company data centre) each offered 20 Gbps uplinks, with link aggregation and M‑LAG peer‑links (two 100 Gb DAC cables). PoE + 30 W supplied power, and UPS units provided backup. Three wireless APs extended corporate‑level network access to the island.

Control System

ZCAM cameras expose a public API for remote control. A custom tool consisting of a Controller (parameter configuration via files or CLI) and a Footage Manager (asset tracking in an external database, automatic deletion when storage thresholds are reached) ensures unattended, long‑duration operation.

Clock & Sync

A GNSS‑enabled Meinberg microSync Broadcast generator receives GPS/BeiDou time, produces BlackBurst, PTP, DARS and LTC signals, and distributes them to all devices. ZCAM EZlink uses PTPv2 to generate genlock clocks, eliminating the need for dedicated timecode cables. Core switches act as boundary clocks, distributing PTP to video, audio, Dante and other AES67/Ravenna devices. Video baseband sync combines BlackBurst and LTC; audio sync uses PTP as primary with WordClock/DARS as backup.

Acknowledgements

Equipment and technical support were provided by Sony (China) Imaging Products, Yike International and Genelec.