What model?
The test specs from Part 91.207 have not changed since the move from 121.5 mhz ELTs to 406 mhz ELTs. Every 12 months it needs to be tested for proper operation, corrosion, operation of the controls AND crash sensor, and for output power.
To do this on a 406 you need a test box. The one I use measures power out on 121.5, 243 (if used), and 406 mhz. It shows when I trigger the accelerometers to trip the ELT 'on'. And, it decodes a bunch of data that shows serial numbers, programming codes, country codes, etc. Most ELTs will also show some I.D. info like N number. A nice perk is that they will also show total time on the battery, so if someone leaves it on for a couple of hours and tries to cover it up, the tester will still show that you need a new battery.
The test box is the only way to actually verify the specs required by 91.207.
Web