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Confidence: Medium · Source: FCC ULS · As of 2026-09-12

W4TF callsign genealogy

Currently held by Singh, Vishnu K

The FCC publishes a previous_call_sign on every amateur license — a self-link to the licensee's prior callsign. Following those links produces the chain below.

Previous callsigns

Older callsigns held by W4TF's current licensee, walking backwards.

  1. AJ4VScancelled· E
    Singh, Vishnu KGAgranted 2009-12-22cancelled 2016-09-07
  2. K4VKScancelled· E
    Singh, Vishnu KFLgranted 2007-03-13cancelled 2009-12-22
  3. KI4TRTcancelled· T
    Singh, Vishnu KFLgranted 2007-02-21cancelled 2007-03-13

Successor callsigns

Callsigns held now by people who previously held W4TF.

No current licensee on record previously held this callsign.

All historical holders

Every license row we've seen with the callsign W4TF, oldest first.

  • GERDES, CHARLES V FL
    2006-09-08 → cancelled 2014-08-18
  • Singh, Vishnu K FL
    2026-09-02 active
← Back to W4TF License history →