Some of you may have seen my earlier posts regarding two of the Velleman mini kits that perform sound to light.
Ideally I want to be able to take a mic level signal and control 2 20w12v lamps. Just like the classic "light organ" circuit.
(For the curious these are going into Dalek 'ears')
So I built this:The MK103 mic to LED light flasher
and this:The 12v light flasher with optoisolator input.
Then I connected one side of the input of the MK114 to the output of the MK103 just after R9. The other input line of the MK114 went to ground.
This seemed to work really well (although I found that running the MK103 at 12v created oscillation in the LED flasher circuit, so I ran the power through a 9v regulator to get it back to running properly).
While I was moving jumpers around I did manage to blow the 557 (T4) transistor in the MK103, this could just have been clumsiness on my part. But it prompts me to ask - is there a mismatch in connecting these two circuits together in this way?
I'm still running the line through both the resistor R9 in the MK103 schematic and R10 in the MK114 - so hopefully current should be limited correctly for the OI.