Confidence: Medium · Source: FCC ULS · As of 2026-09-12
N0SDK callsign genealogy
Currently held by PIERSON, ROBERT N
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 N0SDK's current licensee, walking backwards.
- Krause, Matthew DMOgranted 2015-02-24cancelled 2016-02-12
Successor callsigns
Callsigns held now by people who previously held N0SDK.
No current licensee on record previously held this callsign.
All historical holders
Every license row we've seen with the callsign N0SDK, oldest first.
- PIERSON, ROBERT N MN1992-04-21 → cancelled 2004-04-22
- Krause, Matthew D MO2025-12-30 active