Simple Repeating Strobe Light: Using a single use camera

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Flashing strobe light

Flashing Strobe LightDisclaimer: This project involves high voltages.  If you are not comfortable working with high voltages, do not attempt.  Only attempt at your own risk.

Here are the steps to make a strobe light using a disposable/single-use/one-time use/thow-away camera.  You’ll need one component that may not be available locally–that is SIDAC.  This device will be used as the trigger for the strobe.
The SIDAC used is K1300E70 by Littel Fuse, but you can use any equivalent devices.  Get the TP-92 package.  It fits perfectly.
The flash rate is not readily adjustable.  You can try replacing the big main storage cap to a smaller one will slow the rate.



The camera used in this example is by FujiFilm. Rip and Tear the paper cover off… Caution: Do not press the charge button on the front. That will charge the flash circuit to 200V. If you did, hit the shutter to force the flash. This will discharge most of the voltage, if not all.

 

 

It should look like this. Note the battery in the bottom. Remove the battery. If you want to save the film, wind the film to zero frame and stop. Any further and the film will not be accessible. Just hold the shutter button down while turning the film advance wheel. Keep cranking on that thing! Pop the cover at the bottom to get the film out.

 

 

 

Carefully (or not) remove the plastic case by releasing the various tabs.

 

 

 

 

 

 

 

More tabs…

 

 

 

 

 

…and more tabs, 2 of these in the front.

 

 

 

 

 

 

Remove the cover and you should see the strobe circuitry.

 

 

 

 

 

 

Release the one tab locking the PCB in place and remove the unit carefully.

 

 

 

 

Here is the strobe unit.

 

 

 

 

 

Locate this component.

 

 

 

 

 

The metal contact (red arrow) here will be at about 200V when the circuit is charged up, so avoid touching this tab. Unsolder the component (yellow arrows) and remove it.

 

 

 

 

In its place, install the SIDAC. It’s bidirectional, so it doesn’t matter which way you insert it. Solder it in place. Here is the datasheet for the SIDAC.

 

 

 

 

The hatched area are the charge switch contacts. You need to connect a suitable on/off switch here.

 

 

 

 

Here is the completed unit with battery taped in place and the switch installed.

Remember: 200V! And the trigger voltage gets boosted to around 2000 to 4000V or so, so don’t go pokin’ around!

 

 

 

Afterthoughts
The flash rate is about 1 second, as built here.  You can change the rate by replacing the main capacitor with something smaller to get faster rate.
The SIDAC used is the 130V trip version.  It triggers the flash at charge threshold of 130V.  You can try higher values like 170V.  It might flash a little slower (not verified).  The xenon will not flash below about 120V, so you can’t go too low.  Also, the neon lamp should be left in place in case of some failure, so the charger doesn’t overcharge the cap.
You should only use roughly 1.1V to 1.5V for the power source.  Below 1V, it may not charge up.  Above 2V, it may fry components.  If you want to use higher voltage, you can do few things.  Use step-down dc/dc regulator, linear regulator (will heat up), power diodes(will heat up), power resistor (will heat up), or re-wind the main transformer for higher voltage (not feasible).  The input current looked like about 1 to 2 amps depending on the voltage, so it’s a little power hungry.
Best bet here may be the buck (step-down) converter of about 3A, which you can build or buy from somewhere ready built.  They aren’t too bulky.  The only problem with that is, it may not be able to go down to 1.5V.  MIC4576 (micrel) seems promising.  You’ll have to do some research.