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Need help with stroboscope

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Junior Member level 2
Jul 10, 2002
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discolitez schematic

Hi there,
Could someone help me with providing some shemes about controling frequency of strobo blinking( i don't know how to call it :p ) from LPT port. Can i use modified ? Mainly i need control by volume level.
BIG THX for any help.

Do you already have a strobo and want to modify it (replacing poti by electronics ...) or do you completely build it on your own ? I think this is important to know when thinking about an interface to the lpt-port.



i've already strobo and want to replace poti(220k-1M) by some electronics. If you can make samoe suggestions or provide some schemes i would be very gratefull.

me again:)

i would like to give some new info about my "project". My strobo will be controlled by resistor(poti). How to make resistancy to be changed by freq of digital signal(higher freq of LPT signal will make resistancy bigger). Sory for my bad english. If you don't understand something please wright :).
See you again :p

Is there high voltage at the poti or is it somehow electrically isolated from the power line (I guess not :( ) ??? Is there a transformer or other power-supply between line and strobo ?


check this scheme for more info **broken link removed**
I hope it will be usefull.

I studied your schematic and modified the circuit a little bit. At you can find a proposal how to switch a high-voltage load. They use an opto-coupler (LED & Triac) to separate high-voltage from the low-voltage part (see
Using this coupler I changed you strobos circuit in that way that you can digitally (from the LPT-port) ignite a flash - theoretically. So it should be possible to use DiscoLitez (the winamp-driver) to control the strobo. It's also possible to extend this to 2, 4 or more strobos (up to 32 for the deluxe-version :lol: ).
But if you don't want to use DiscoLitez you can write a small program to output a square-wave at the LPT-port and control the strobo in that way.

The circuit is not tested !!! So please Elektroda-Freaks take a look at it and make some comments, suggestions, improvements !!!

There is for example one question: What will happen if the couplers LED is powered (LPTs D0=high) and C3 is beginning to charge (after an igniton).
Will TH1 switch if a certain voltage-level at C3 is reached ? This could lead to uncontrolled flashes and we somewhere have to add a capacitor to form a short pulse ?!?


According to **broken link removed** no points are needed for a look :arrow:

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