Is there anything wrong with coupling these two circuits?

[Kasterborus]

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 20w
12v lamps. Just like the classic "light organ" circuit.

(For the curious these are going into Dalek 'ears')

So I built this:

http://www.stephenhobley.com/sound.jpg
The MK103 mic to LED light flasher

and this:
http://www.velleman.be/images/tmp/MK114.jpg
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.

Thanks,
Dave

 

[petrus bitbyter]

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 20w
12v lamps. Just like the classic "light organ" circuit.

(For the curious these are going into Dalek 'ears')

So I built this:

http://www.stephenhobley.com/sound.jpg
The MK103 mic to LED light flasher

and this:
http://www.velleman.be/images/tmp/MK114.jpg
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.

Thanks,
Dave

If you raised the power supply of the MK103 to 12V and connected the input
of the MK114 parallel to the LEDs of the MK103 it might have caused the
transistor damage and blow. Especially when you moved replaced R10 of 1k by
a 330 type and turned RV1 of the MK114 too high or too low. You'd better
replace LD4 of the MK103 by the LED of MK114s 4N35. You may have to turn RV1
of the MK102 for a usefull light on the MK114. The best value for the LEDs
LD1-LD3 to light is not necessarily the best value for the lamps driven by
the MK114.

petrus bitbyter

 

[ElPerfecto]

I'd love to see how you could get the MK103 to run with 20W lamps instead of LEDs. If you get it working, please post your results. I just finished building my unit and posted a review of the unit (at elperfecto.com) along with a video showing it in operation. I would also like to modify the circuit, like maybe put the mic outside to listen for loud sounds triggering the LEDs inside my house... like some kind of home security system, but mostly for play.

 

[neon]

Why biuld this thing with individual transistor ? An IC differetial amp will sufice for the gain. then use MC3020 to run from 120v ac because if this thing works ever it is going to be a very short time display. I guess you never heard of Ico with those value it mey come into play. WHY the 47 ohms and big cap you realy think that you can move a 9v battery. read books.