STM32 control board
On the right - the board on STM32 (SSOP-20). On the left - similar functionality on ATTINY13 (DIP-8).
The test board is a worn-out, soldered-resoldered 10 times sample, on which characteristics, logic, load, etc. are tested.
The final version is soldered once, tested already in the directly executable form, so its condition is much better.
These boards work in their places, and we keep the test sample for ourselves, just in case - and here it is - we took a photo for demonstration, even though it looks "not exhibition-worthy" :)
The test board is a worn-out, soldered-resoldered 10 times sample, on which characteristics, logic, load, etc. are tested.
The final version is soldered once, tested already in the directly executable form, so its condition is much better.
These boards work in their places, and we keep the test sample for ourselves, just in case - and here it is - we took a photo for demonstration, even though it looks "not exhibition-worthy" :)
Vinnytsia 
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