Confidence: Medium · Source: FCC ULS · As of 2026-09-12
WA1SHM callsign genealogy
Currently held by Walsh, Mark S
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 WA1SHM's current licensee, walking backwards.
- Walsh, Mark SMAgranted 2002-08-30cancelled 2003-04-25
Successor callsigns
Callsigns held now by people who previously held WA1SHM.
- Hyatt, David BCTgranted 2017-12-06
All historical holders
Every license row we've seen with the callsign WA1SHM, oldest first.
- Walsh, Mark S MA2024-04-19 active
- HYATT, DAVID B— → cancelled 1998-02-26