Since you've played with "unnaturally" huge amount
of 2N2369A transistors lately when preparing the cal kit, just curious, are there any huge variations on the tR between them ? Also the voltage where it starts to avalanche, did you just set it at fixed voltage at all boards, or you tweaked the voltage each of them ?
If there is a Guinness book of record on tweaking amount of 2N2369A for avalanching purpose, I'm guessing you must be the winner.
....j/k
Thanks !