With the following method an 8 character amateur radio callsign can be encoded in a 48 bit ethernet address. It also allows for a 4 bit secondary station id. The different characters are encoded using a base37 encoding.
| 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35 | 36 |
| 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | null or whitespace character |
| 0 - 7 | 8 - 15 | 16 - 23 | 24 - 31 | 32 - 39 | 40 - 47 | |||
| 48 bit ethernet address | ||||||||
| callsign bit 41 - 40 | 4 bit SSID | locally administered bit | multicast bit | callsign bit 39 - 32 | callsign bit 31 - 24 | callsign bit 23 - 16 | callsign bit 15 - 8 | callsign bit 7 - 0 |
The locally administered bit is always on. The multicast bit can be used when appropriate.
For example, the callsign PE1RXQ results in the following address: c2:31:a6:64:88:92