Confidence: Medium · Source: FCC ULS · As of 2026-09-12
KO0K callsign genealogy
Currently held by CHEN, GUOCE
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 KO0K's current licensee, walking backwards.
Successor callsigns
Callsigns held now by people who previously held KO0K.
No current licensee on record previously held this callsign.
All historical holders
Every license row we've seen with the callsign KO0K, oldest first.
- Hawkins, Benjamin F OH2006-07-25 → cancelled 2007-01-24
- CHEN, GUOCE KS2010-04-17 → cancelled 2022-04-19
- Karjanlahti, Mika MN2022-05-06 active