MK 100 Christmas Tree Help Needed


Have you checked the continuity for that side of the circuit?

When I was trouble shooting mine I wrote down some of the voltages.
the problem will be on the left side.
Your voltages maybe different but should be close.
Where there are 2 voltages that would be on and off.


Many thanks - I’m away from home now but will test the voltages when I get home and let you know the result!!



Out of interest, what was the fault you finally found on yours? That might give me a clue!!



I broke one of the traces away from the pad.
I checked the continuity from pad to pad until I found it.


Thanks - by “traces” do you mean the printed circuit connections from one soldered connection to another??


Well…the moral of this story is don’t let your 3 year old grandson near any electronic projects!! Hugo (for it was he) gleefully held the flashing Xmas tree in his hand and, without me realising, had proceeded to wiggle one of the capacitors so much that it had broken the track it was soldered to! All fixed now and flashing away merrily (and out of reach of the grandchildren!!) Thanks for all the advice.

Incidentally I am fascinated how this circuit, which on the face of it it two push-push circuits together, manages to change the flashing sequence without the use of an IC in the circuit - clever stuff…!!

All good wishes,



Sorry I haven’t been around
Glad to hear it’s working again