Confidence: Medium · Source: FCC ULS · As of 2026-09-12
K1US callsign genealogy
Currently held by HARDER, JON G
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 K1US's current licensee, walking backwards.
- Mueller-Harder, Erik DVTgranted 2006-02-07cancelled 2007-08-11
Successor callsigns
Callsigns held now by people who previously held K1US.
No current licensee on record previously held this callsign.
All historical holders
Every license row we've seen with the callsign K1US, oldest first.
- HARDER, JON G VT2001-04-25 → cancelled 2004-01-26
- Mueller-Harder, Erik D VT2017-06-06 active