Confidence: Medium · Source: FCC ULS · As of 2026-09-12
WA6SDM callsign genealogy
Currently held by HOLLENBACK, M JAMES
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 WA6SDM's current licensee, walking backwards.
- KN6QWWcancelledL A County DCS San Dimas StationCAgranted 2021-10-04cancelled 2021-10-26
Successor callsigns
Callsigns held now by people who previously held WA6SDM.
- HOLLENBACK, M JAMESWAgranted 2018-02-02
All historical holders
Every license row we've seen with the callsign WA6SDM, oldest first.
- L A County DCS San Dimas Station CA2021-10-26 active
- HOLLENBACK, M JAMES— → cancelled 1998-03-03