Confidence: Medium · Source: FCC ULS · As of 2026-09-12
KC9SDR callsign genealogy
Currently held by Johnson, Michael R
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 KC9SDR's current licensee, walking backwards.
- Johnson, Michael RILgranted 2010-04-01cancelled 2010-04-21
Successor callsigns
Callsigns held now by people who previously held KC9SDR.
- Johnson, Michael RILgranted 2020-02-11