{
  "url": "https://proudtek.com/products/rfid-keyfobs/dual-frequency-key-fob/",
  "sourceUrl": "https://proudtek.com/products/rfid-keyfobs/dual-frequency-key-fob/",
  "title": "Dual-Frequency Key Fobs — One Credential, LF + HF",
  "description": "Dual-frequency key fobs embed two electromagnetically-isolated RFID chip-antenna systems — a 125 kHz LF transponder (EM4100 / T5577 / HID Prox...",
  "kind": "product",
  "imageUrl": "https://proudtek.com/landing-images/dual-frequency-key-fob.png",
  "imageAlt": "Dual-frequency RFID key fob with LF and HF chips",
  "imageGallery": [
    {
      "url": "https://proudtek.com/landing-images/dual-frequency-key-fob.png",
      "alt": "Dual-frequency RFID key fob with LF and HF chips"
    }
  ],
  "breadcrumbs": [
    {
      "name": "Home",
      "url": "https://proudtek.com/"
    },
    {
      "name": "Products",
      "url": "https://proudtek.com/products/all/"
    },
    {
      "name": "Dual-Frequency Key Fobs — One Credential, LF + HF",
      "url": "https://proudtek.com/products/rfid-keyfobs/dual-frequency-key-fob/"
    }
  ],
  "summary": [],
  "faq": [
    {
      "question": "Is the fob bigger than a standard single-frequency fob?",
      "answer": "Only slightly. Our dual-frequency fob is 40×32×6 mm — about 1 mm thicker than a standard single-frequency fob. The size difference is imperceptible on a keychain. The dual antenna design fits within the standard fob form factor through careful coil positioning."
    },
    {
      "question": "Can you match our existing fobs?",
      "answer": "Yes. Send us samples of both your LF and HF fobs (or tell us the reader models) and we produce a single dual-frequency fob that matches both. We provide a UID correlation table linking the LF and HF chip IDs for each fob."
    },
    {
      "question": "How do I program both chips?",
      "answer": "Each chip is programmed independently using its respective frequency reader/writer. We can pre-encode both chips at our factory. Provide your LF credentials (facility code, card number) and HF credentials (sector keys, access data) and we program everything before shipment. A UID mapping file is included with each order."
    },
    {
      "question": "Does the LF chip interfere with the HF chip during a dual-frequency scan?",
      "answer": "No. The two antennas are tuned to very different frequencies (125 kHz and 13.56 MHz — two orders of magnitude apart) and the coil geometries are designed for electromagnetic isolation. Each chip only responds to its own band; a 125 kHz reader energises only the LF coil and a 13.56 MHz reader energises only the HF coil. ProudTek verifies isolation per unit during production by running both chips against a test reader of each frequency and rejecting any unit where cross-coupling affects sensitivity by more than 1 dB."
    },
    {
      "question": "What's the typical migration timeline with dual-frequency fobs?",
      "answer": "A typical enterprise LF-to-HF migration runs 12-18 months. Phase 1: issue dual-frequency fobs to all users in a single re-issuance event (zero access disruption because both chips work). Phase 2: roll out new HF readers building by building over 6-12 months. Phase 3: firmware-cut-over to disable LF mode on the dual-frequency credential (or simply retire the LF reader fleet) and operate HF-only. Because users carry the same fob throughout, there is no second issuance event and no mid-migration access interruption — this is the pattern ProudTek's logistics-operator and corporate-campus references ran through."
    }
  ],
  "procurementFields": [
    {
      "label": "Best fit",
      "value": "Best for access control, parking, elevator, and membership credential projects."
    },
    {
      "label": "Key options",
      "value": "Form Factor: Compact keyfob form factor for handheld access credentials."
    },
    {
      "label": "Customization",
      "value": "Confirm artwork, encoding, material, chip, and finish requirements before quoting."
    },
    {
      "label": "Quote checklist",
      "value": "Reference Dual-Frequency Key Fobs — One Credential, LF + HF in your inquiry so the matching product page stays attached to the quote. Compact keyfob form factor for handheld access credentials. Share target chip or protocol, quantity,..."
    }
  ],
  "collectionGuidanceFields": [],
  "coreGuidanceFields": [],
  "articleGuidanceFields": [],
  "sourceLinks": [],
  "related": [],
  "productSpecs": [
    {
      "name": "Form Factor",
      "value": "Compact keyfob form factor for handheld access credentials."
    }
  ],
  "machineJsonUrl": "https://proudtek.com/machine/products/rfid-keyfobs/dual-frequency-key-fob.json",
  "machineTextUrl": "https://proudtek.com/machine/products/rfid-keyfobs/dual-frequency-key-fob.txt",
  "author": {
    "name": "Proud Tek Co., Limited"
  },
  "publisher": "Proud Tek Co., Limited",
  "credentials": [
    "ISO 9001:2015",
    "ISO 14001:2015",
    "RoHS Compliant",
    "CE Marking",
    "REACH Compliant"
  ],
  "generatedAt": "2026-03-16T01:42:30.697Z"
}