On Wednesday, May 22, 2019 at 9:16:45 PM UTC-4, wrote:
This website discusses it, but never really identifies the part. This is
the meter I am working on and I too wondered what the SA1 and SA2 parts
are. I never saw that symbol.
https://www.antiqueradios.com/forums...c.php?t=117824
Schematic on the webpage.
Wild guess: spark gaps for protection.