{
  "type": "crystal",
  "specs": [
    {"name": "frequency_hz", "description": "Nominal frequency", "unit": "Hz", "required": true},
    {"name": "load_capacitance_f", "description": "Specified load capacitance (CL)", "unit": "F"},
    {"name": "esr_ohm", "description": "Equivalent series resistance (ESR)", "unit": "ohm"}
  ],
  "subtypes": {
    "crystal": {
      "description": "Crystal / crystal oscillator",
      "extra_specs": [
        {"name": "frequency_stability_ppm", "description": "Frequency stability/tolerance", "unit": "ppm"},
        {"name": "drive_level_w", "description": "Maximum drive level", "unit": "W"},
        {"name": "shunt_capacitance_f", "description": "Shunt capacitance (C0)", "unit": "F"}
      ]
    }
  }
}