Confidence: Medium · Source: FCC ULS · As of 2026-09-12
K4TWN callsign genealogy
Currently held by Sparks Sr., Jason C
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 K4TWN's current licensee, walking backwards.
- White, Michael JTNgranted 2023-04-19cancelled 2024-05-10
Successor callsigns
Callsigns held now by people who previously held K4TWN.
- Sparks Sr., Jason CCAgranted 2019-12-13cancelled 2021-02-23
All historical holders
Every license row we've seen with the callsign K4TWN, oldest first.
- Sparks Sr., Jason C CA2019-11-19 → cancelled 2019-12-13
- White, Michael J TN2024-05-10 active