Confidence: Medium · Source: FCC ULS · As of 2026-09-12
KB3MHR callsign genealogy
Currently held by Ruback, Mitchell H
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 KB3MHR's current licensee, walking backwards.
- Ruback, Mitchell HPAgranted 2007-10-04cancelled 2007-10-30
Successor callsigns
Callsigns held now by people who previously held KB3MHR.
- W3NIHactiveNational Institutes Of Health Radio Amateur ClubMDgranted 2025-05-07
All historical holders
Every license row we've seen with the callsign KB3MHR, oldest first.
- National Institutes Of Health Radio Amateur Club MD2005-05-23 → cancelled 2005-06-24
- Ruback, Mitchell H PA2017-08-03 active