I'm such a slow builder that the batteries in the ELT have timed out, so I need to replace them to be legal. There are three in total, starting with the one in the remote indicator in the panel:
In addition to making entries in the aircraft logs, I put stickers showing the battery expiration dates on the side of each component:
The main battery pack for the ELT itself is huge and expensive:
Despite the expense, a replacement ACK ELT battery pack doesn't come with the required o-ring, so I re-lubed and reused the old one:
The third battery is in the audio alert unit, which I quickly regretted installing on the aft side of the F-707 bulkhead where it couldn't be seen:
When I reinstalled all these units I moved the audio alert unit to the front side of the bulkhead, so it will be slightly easier to service next time:
And while I was crawling way back in the tailcone, I fitted the ELT antenna static suppressor that's now apparently required by a service bulletin:
