Scalextric Digital (APB, ARC PRO)
This is a DIY modification. Difficulty level 3/10, this is only really a little bit of easy soldering…
This thread is how to make a digital 4 lane start for the C7042 using parts salvaged from a C7030 (the old 6 car powerbase).
You need:
1x C7042 updated to the latest v1.009 firmware...