OperGrid

A flat-file PHP signup grid for amateur radio operating events.

This tool is intended to be a "quick and dirty" signup method for integration into a larger online ecosystem for a radio club or similar organization. As such, it does not have any form of real security, accounts, abuse-protection, etc. Please be thoughtful when deploying this.

Main Files

opergrid/
├── public                ← root/DocumentRoot for webserver
      ├── index.php       ← Main UI (the grid)
      ├── api.php         ← REST API (read/write signups)
├── data
      ├── config.json     ← Event config: stations + schedule
      ├── signups.json    ← Signup data (auto-created / editable)
└── config.php            ← Core configuration

Requirements

• PHP 8.x-enabled webserver write permission to the directory data/

Setup

1. Copy all files to a reasonable location (e.g. /var/www/opergrid/)
2. Make sure the data directory is writable by the same userver as the webserver. For example on Debian the user is www-data:

   chmod 755 /var/www/opergrid/data
   chmod 664 /var/www/opergrid/data/*.json
   chown -R www-data:www-data /var/www/opergrid/data/

3. Edit config.json to set your event details, stations, and hours.
4. Edit your webserver configuration to serve the contents of /var/www/opergrid/public either as the root of the site or using an appropriate sub-director rewrite/Location. Restart when complete.
5. Open the location in your browser.

config.json Reference

The event label is simply the title.

The stations[] is an array of values:

• id - The unique ID for the station, limited to [a-zA-Z0-9], max 10 chars, must be unique
• name - The title for this item
• band - The band label
• mode - The mode for the operation
• schedule - (Optional) Specify one or more times this station is avalable, bounded by the overall schedule. If absent, the station's schedule is the full range of the event schdule.

Here's an example showing different combinations:

{
  "event": {
    "name": "Field Day 2026"
  },
  "stations": [
    { "id": "sta80", "name": "80m Station", "band": "80m",  "mode": "Any" },
    { "id": "sta40", "name": "40m Station", "band": "40m",  "mode": "Any",
      "schedule": { "start": "2026-06-27 18:00", "end": "2026-06-28 12:00" } },
    { "id": "sta20", "name": "20m Station", "band": "20m",  "mode": "Any",
      "schedule": { "start": "2026-06-27 14:00", "end": "2026-06-28 02:00" } },
    { "id": "sta15", "name": "15m Station", "band": "15m",  "mode": "Any",
      "schedule": [
        { "start": "2026-06-27 14:00", "end": "2026-06-27 22:00" },
        { "start": "2026-06-28 08:00", "end": "2026-06-28 12:00" }
      ] },
    { "id": "sta10", "name": "10m Station", "band": "10m",  "mode": "Any",
      "schedule": [
        { "start": "2026-06-27 14:00", "end": "2026-06-27 20:00" },
        { "start": "2026-06-28 10:00", "end": "2026-06-28 12:00" }
      ] }
  ],
  "schedule": {
    "start": "2026-06-27 14:00",
    "end":   "2026-06-28 12:00",
    "tz": "EDT (UTC-4)"
  }
}

Day boundaries are automatically highlighted in the grid with an amber divider line and a date label (e.g. "Sat 6/28") in the time column.

The ID must be no more than 10 characters.

signups.json Format

Keys are stationId|HH:MM. Written automatically by api.php.

{
  "sta1|08:00": {
    "name": "Jane Smith",
    "callsign": "W1XYZ",
    "email": "jane@example.com",
    "claimed_at": "2026-04-01T10:23:00+00:00"
  }
}

These fields are limited to 30 characters each except callsign which is limited to 10 characters. Fields will be auto-truncated as necessary.

API Endpoints

Method	URL	Description
GET	api.php?action=config[&event=ID]	Returns config.json
GET	api.php?action=signups[&event=ID]	Returns all signups
POST	api.php?action=claim[&event=ID]	Claim a slot

POST claim body

{
  "station": "sta1",
  "timeslot": "08:00",
  "name": "Jane Smith",
  "callsign": "W1XYZ",
  "email": "jane@example.com"
}

Resetting Signups

Simply replace signups.json with {} to clear all signups.

Multiple Events

OperGrid can handle multiple events at the same time. By default, the system uses an event name of "default" internally which uses the config.js and signups.js files listed above.

However, the URIs can have an event= parameter which will cause the system to ouse a different set of files, thus effectively creating a separate event. For example event=foo will cause the use of config_foo.js and signups_foo.js (Note that the underscore _ is added automatically). One can create as many arbitrary config_$event.js files as needed. There is no main menu to find/select events however as, again, this is intended to be used within a large web ecosystem.