My telraam v1 recently died. I noticed it right after a lightning storm, so I assume this had something to do with it. The device is located outside.
I ordered a new pi3 A+ and assumed that it would be a simple swap of the board but it turned out differently.
I kept the SD card and used this with the new board. Unfortunately it wouldn’t boot and the ACT LED blinked in a certain pattern. I had the suspicion that the new board probably behaved a little different than the old one and did no longer support the older Raspbian version used by telraam v1.
After lots of trial and error I finally found this post: Stretch not booting on 3B+ . This was a confirmation of my suspicion, the newer boards don’t work with the older Debian stretch based image of telraam v1. After copying the start*.elf, fixup*.dat and bootcode.bin files from the newer Bullseye image to the boot directory, my telraam v1 booted successfully again!
This could be a helpful tip for all those that have to replace a defective board with a newer one.