Confidence: Medium · Source: FCC ULS · As of 2026-09-14
W3KLR callsign genealogy
Currently held by Gross, Isadore
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 W3KLR's current licensee, walking backwards.
- Keller Jr, William SPAgranted 2017-03-15cancelled 2017-05-02
Successor callsigns
Callsigns held now by people who previously held W3KLR.
No current licensee on record previously held this callsign.
All historical holders
Every license row we've seen with the callsign W3KLR, oldest first.
- Gross, Isadore PA2003-12-03 → cancelled 2016-03-02
- Keller Jr, William S PA2017-05-02 active