A friend pointed me to this log about making PCBs of the Singapore, Tokyo and SF Bay Area systems. One for those keen on transit systems.
it seems to be some large pcb surface
How are the LED’s soldered (top/bottom side?) quite good solution !
What is the fare for a (local-3 stops) ride on a dual op amp?
This project also made it’s way to Hackaday:
Thanks for the link and stackup description which is used.
Probably would be quicker (for him and others interested in such an interesting technics and ‘great idea’ - I love such ideas!), with less effort:
to ‘replace the MDM layer’ by an ‘FR4 blank PCB’ which could simplify the efforts…
By having already the ‘cuts-edge of bottom layers’ (the one used for the top silk-screen), to duplicate it with no tracks at all*.*
Even further using some SMT RGB 0402 leds on the bottom PCB that fit the holes on the top PCB (if this ‘third layer’ MDM or FR4 could be avoided, which could also simplify the final assembly).
The PCB Manufacturer will have most probably no difficulties to manufacture all of these different PCB’s of the same format (which could be panelized).
Could be a way (when hundreds of them would be needed to be manufactured…).
FYI: A solution I use on my side (to protect my PCB’s, when not using any box, avoiding a ‘PCB boxing phase’ which would be useless, depending the final use…).