signalling for major errors for outside multigeigers?
related to #201.
the problem is here that after the multigeiger is (finally) deployed to the outside, nobody will look at the display usually and only very rarely at the ESP32 web interface.
audio would work slightly better, a beeping device would get some attention (of course should be only used for serious errors).
I know this from UPS devices and RAID controllers. Sometimes only the thing beeping successfully draws attention (if the battery is dead or disks have failed).
RGB LED (see #106) blinking could also work, as this is visible from a distance.
online upstream notification would also work, IF an email notify is triggered server side ("please look after your multigeiger device ID: ESPxxxxxxxxxx").
also related: #257