Downlink Desk – Introduction
Purpose
This manual tells operators how to run Downlink Desk, a ground-segment operations console for satellites tracked through the SatNOGS network. It covers starting a shift, responding to alerts, changing limits, handing over, checking the audit trail and isolating common faults.
About this publication
This is a demonstration manual. It was written to show how structured technical documentation works, using Downlink Desk, an open-source hobby console, as its subject. Downlink Desk watches real satellites, but it is not used by any mission team, and this manual is not an approved procedure for any real operation.
Using this manual with the public demo
The public demo at archer7778.github.io/downlink-desk shows real telemetry, but it is a read-only snapshot rebuilt about every 6 hours. You can follow the descriptive modules and look at every screen the procedures name. Steps that sign an action, such as acknowledging or shelving an alert, completing the daily check, changing limits or signing a handover, show the message "This is a read-only demo" instead.
To carry out the procedures in full, install Downlink Desk on your own computer. Fault isolation steps marked "on the server" also need your own installation.
The demo also has a training simulator at archer7778.github.io/downlink-desk/training, where you can inject faults and practise responding to them. Its screens differ from the console, and this manual does not cover it.
Who this manual is for
Operators who watch one or more satellites on a running Downlink Desk console. You do not need to know how the software works inside. For installation, see the setup guide in the Downlink Desk repository.
Applicability
This issue applies to Downlink Desk version 0.17.x running on Debian, Ubuntu or Raspberry Pi OS. Screens and commands may differ in later versions.
How the manual is organised
The manual is made of data modules. Each data module covers one topic and has its own code, issue number, date and status. There are three types:
Descriptive modules explain what the system is and how it behaves.
Procedural modules give numbered steps for a task, with the requirements you need before you start and the conditions when you finish.
Fault isolation modules take you from a symptom to its cause through yes/no questions.
Data module codes
Each data module code follows the S1000D pattern. For example, DMC-DLD-A-20-10-00-00A-130A-A is read as:
| Part | Value | Meaning |
|---|---|---|
| Model identification code | DLD | Downlink Desk |
| System difference code | A | The standard installation |
| System, subsystem and sub-subsystem | 20-10 | Alert system, alerts (see the numbering table below) |
| Assembly | 00 | Not broken down further |
| Disassembly code and variant | 00A | Not broken down further; first variant |
| Information code and variant | 130A | Normal operation; first variant |
| Item location code | A | Information about the item as installed |
The system numbering used in this manual:
| Number | System |
|---|---|
| 00 | Downlink Desk as a whole |
| 10 | Data collection: 10-10 SatNOGS link, 10-20 telemetry reception |
| 20 | Alert system: 20-10 alerts, 20-20 channel limits |
| 30 | Operator console: 30-00 web console, 30-10 shift start, 30-20 shift handover, 30-30 audit trail |
The information codes used are 005 (list of abbreviations), 006 (list of terms), 012 (safety statements), 018 (introduction), 040 (description), 130 (normal operation), 300 (examinations, tests and checks) and 400 (fault reports and isolation procedures).
Conventions
Names of buttons, tabs and fields on screen are shown like this: Acknowledge.
Commands you type on the server are shown like this:
sudo systemctl restart downlink-desk-web. They assume Downlink Desk is installed in~/downlink-desk, as in the setup guide.Safety statements follow S1000D. A warning tells you about a risk of injury or death; this manual has none. A caution tells you about a risk of damage to equipment or data, or of an incorrect record. A note gives useful information.
The console also uses Caution and Alarm as the names of its two alert severities. These are shown as screen text, and are not safety statements.
Each data module shows its quality assurance status. Unverified means the procedure has been checked against the Downlink Desk source code but has not yet been carried out on a running console.