MK103RS Sound-to-Light Unit not lighting up

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1

I’ve just built this kit and it doesn’t seem to be working at all.
I’ve read some of the topics and found no solution and thought maybe id just post myself :0)

Here are some pics.
lionellswebsite.com/1.jpeg
lionellswebsite.com/2.jpeg

Thanks for your help.

2

Resistor placement looks OK.
Make sure transistors are correct (BC547 & BC557 not interchanged)
Some solderings need some re-work. Gently heat all of them again an apply a little solder when necessary.
Watch for solder bridges (two pads connected which should not be connected).

3

Hey, I just found a gotcha in this kit (don’t ask how I found it). There are 2 (!) different types of transistors in the circuit. The components look exactly the same, except for the markings, and the numbers are only different by one digit. T4 is different from T1, T2 and T3. If you thoughtlessly switch T4 with one of the others, the circuit will not work properly. Hope this info helps someone.