Confidence: Medium · Source: FCC ULS · As of 2026-09-14
KN4IWR callsign genealogy
Currently held by Waldorf, Ivan 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 KN4IWR's current licensee, walking backwards.
- Waldorf, Ivan RNCgranted 2019-05-28cancelled 2026-02-18
Successor callsigns
Callsigns held now by people who previously held KN4IWR.
- Montfort, MarcFLgranted 2020-03-07
All historical holders
Every license row we've seen with the callsign KN4IWR, oldest first.
- Montfort, Marc FL2018-01-16 → cancelled 2020-03-07
- Waldorf, Ivan R NC2026-02-18 active