Confidence: Medium · Source: FCC ULS · As of 2026-09-12
N4UDP callsign genealogy
Currently held by ACKERMAN, HANS C
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 N4UDP's current licensee, walking backwards.
- Haworth, Matthew CCAgranted 2019-12-16cancelled 2020-01-18
Successor callsigns
Callsigns held now by people who previously held N4UDP.
No current licensee on record previously held this callsign.
All historical holders
Every license row we've seen with the callsign N4UDP, oldest first.
- ACKERMAN, HANS C VA1998-10-23 → cancelled 2010-10-26
- Haworth, Matthew C CA2020-01-18 active