This Chinese national standard specifies technical requirements, measurement methods, and functional checks for cable digital TV set‑top boxes.
The standard GY/T 240—2009 defines the scope, normative references, and abbreviations for cable digital television set‑top boxes. It outlines the technical requirements that the devices must meet, including appearance, functionality, video/audio performance, and interface specifications.
It also provides detailed measurement methods, test conditions, and environmental requirements such as temperature and humidity limits. Appendices give normative details for EPG SI tables and ASI output interface requirements, and a reference list cites related GB and GY standards. This manual is written in Chinese.
| Video output amplitude | 700±30 mV P‑P |
|---|---|
| Audio output level | ≥‑8 dBu |
| Operating frequency range | 111–862 MHz |
The video output amplitude must be 700 ± 30 mV peak‑to‑peak.