DIY Strobe Light

[donkey]

Good for you! Getting started in electronics can be tricky. I started with a similar book from radio shack a while ago. I worry a bit about your colour selection, as red gets attenuated pretty quickly under water (though I do have a red led princeton tech tank marker...silly me).

As for sealing it up, flooding the case with silicone might block a lot of the light, depending on how things go together. A slow-setting epoxy (1hr, maybe) might also work, but would make it pretty hard to change the battery!

I hope this doesn't sound too negative...

 

[tonygagey]

Thanks for the encouragement Donky, I have changed the red LED for a 12000mcd White LED it seems ok ,my thoughts on silicone are to:
A) prevent/reduce moisture damage.
B) Give some shock Protection.
C) hold the board in place in a tube or box (Waterproof housing0.
D) Isolate the electrics from the batt to give some chance of saving them in the event of a flood.
As to the "Lens" of the strobe I was thinking of composite Rings of perspex.

 

[donkey]

I agree with the need/desire to protect the electronics from moisture damage. Were you thinking a silicone lube (o-ring lube) or an RTV silicone that will harden? In my experience, the former is extremely messy, while the latter is challenging to work with to get full coverage and a proper seal. I wouldn't worry about protecting the circuit from mechanical shocks. LEDs are extremely resilient is this respect. I have had good luck placing small electronics boards in tic-tac boxes and flooding them with a 2-part potting compound. I used some fancy stuff specifically made for potting, but a slow-set epoxy should be easier to find and should work reasonably well.

re. the lens: typically LED output patterns are directional, especially in high output devices that I've seen. If you have a few to experiment with it might be worth trying to modify the plastic lens that it already has in order to direct more light out the sides. I have no idea how well this forum will render ascii art, but I'll try:

Typical led lens:
...__
./....\
|......|
|......|
-------

Modified by drilling a counter-sink

|\..../|
|.\_/.|
|......|
-------

I have seen commercially available LEDs with lenses like this, so I'm not totally off my rocker with this idea. Your perspex rings would probably get more light directed into them this way, but I've never actually tried this so I may be full of it.

 

[MikeFerrara]

Got a book on electronics(Electronics for dummies) it had a plan for a flashing led light, got the parts; so far built three with some success. cost about £1(2$) each! now just need a housing......
Thinking of encasing the electrics in silicon first?

No reason it shouldn't work. Any astable vibrator circuit should do it. I'm not sure what's available now but in the old days a 555 would have been an easy way to handle the timming.

LOL, but I think all those strobes are going to be hard on the poor folks you dive with. There are few things more unpleasant than trying to dive with a strobe in my face. Marking a line is one thing but I don't think divers need to dress themselves in flashing lights.

 

[tonygagey]

I will give it a try and see how it comes out might be a while before I get round to it though she how must be obeyed (wifey)is giving me more to do round the house as she thinks I have tomuch time on my hands to enjoy myself with!!!