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I've built a few disposable camera strobes, and want to use them in solar garden lights, instead of LEDs. Answered

 My problem is getting them to switch ON after dark. 

The strobes draw about a half an amp, when the first start to charge.  A single AA rechargeable battery should last a few hours, but no idea on how do the switching with only 1.2 volts.  Any help or suggestions? 

Was hoping to get a half dozen put together before Halloween, sort of a lightning-effect.?


I don’t know the specks of your strobe but I assume you used an optocouplier or a transistor between the indicator led and the flash button.

Try this circuit, it is much the same as a solar garden light only it turns on the strobe through the optocouplier.


Doubtful there is a 1.2 volt/half amp switching scheme, or just don't know where to look. Started wondering if there is a low current means to disable the blocking-oscillator inverter on the flash board. Need to look into it a little more, but would hope that if it doesn't oscillate, maybe it won't draw much current. Past week at work was a bummer, not a lot of volume, but got visitor coming all next month, and we have to do a lot of extra cleaning and painting for the next few weeks. The place doesn't look bad, but they want it to look fresh and new. Personally, I think it gives a better impression to leave it looking like we work, and keep the place nice, than recently scrubbed and covered up with paint. It's a warehouse... Anyway, was thinking maybe a photodiode across the inverter transistor might keep it shut off during daylight, and give normal function at night. Unfortunately, my disorganized parts bin, leaves me wondering which are photodiodes, and which are IR LEDs...

Used disposable cameras can be had for free for the asking, at most places that process them. You add a 20 cent SCR and a jumper, and you get a very slow rate strobe, about 30 seconds between flashes. No two flash at the same rate, so multiples make for a nice lightning effect. Much brighter than LEDs or Christmas bulbs. Was hoping to do the solar garden lights, so the are automatic, might even be good for scaring off stray cats using my backyard for a toilet (dog does a fair job, when we see them in the act).

I could tie them into my 12 volt solar lighting, but would require running wires and a buck regulator. Or I could go out and switch them manually, or replace the batteries. I was hoping to find a more less expensive, and interactive solution, which is why I posted this.

It's just really difficult for me to find such a low voltage, high current, switching scheme. I did get one camera, that had 2 AA batteries, and worked off the 3 volts, which puts me in the position of using a small reed relay, but the solar panel doesn't put out much current to charge the batteries, and maybe just high enough voltage to charge two batteries. All the other cameras were Kodak, and single batteries, my garden lights are all single battery as well, so would rather stick with that. The solar lights are chosen, because the provide a weatherproof housing, and everything else required.

strobe lights will only flash a limited number of times, then the bulb needs replacing pretty quick. i made a strobe flash for halloween once and it only flashed one day. The next day, i switched to small christmas lights such as the large size found on christmas trees. The kind that are only about one or 2 watts per bulb. You could use only the blue ones and set them to flash randomly to simulate lightning and they will be cheap and easy to replace when they burn out. If you use larger bulbs, they don't turn off as quickly due to their large filiament, so it doesn't look like lightning. So the smaller bulbs are better, just use more of them. If you only want the STROBE to flash very in-frequently... then it might work out ok to use the strobe type bulbs.

If you want them on after dark for Halloween, I suggest just switching them on. The garden lights are designed to save the hassle of switching every day.


Uhm. Be aware that strobes at some flash rates can trigger epileptic seisures in some folks, and really should NOT be used in a situation where they can't be avoided without getting permission from everyone first.