I may just get another flash unit for backup if nothing else. I'd like to see if I can figure this puzzle out as part of my initiation into electronics. I don't think the springy thing is for a trigger as there is no button position near that on the case. Well the worst that can happen is a capacitor blows up right As far as getting hot it is my understanding that all magnetic pulsers get hot..which is why they they give warnings in their instructions. Well I pushed the envelope and pffffut.....no more flasher.
Although the cap test esr good I'll give it a once over and report back if I am successful. Thanks for your help.
I agree, this is the best way to learn but it makes it more challenging if there are few unknowns in the equation. That's the reason I always try to change one thing at the time so it is easier to track any problem.
Originally Posted by medusa
So, you're saying that the only way it can be triggered is by the foot mount from camera? No other button on the case? There is a hot, HOT and really HOT, LOL. Although, these flashes are not very powerful. Due to the small battery it takes a few seconds to charge capacitor, so it can "relax" between pulses. Professional lamps have big storage and can fire couple pulses in very short time. I suspect that your flash cannot fire more frequent than once per 7 seconds.
Now, I'm puzzled with this spring contact on the board. Is there anything in the case what could push it towards the pin? Could you follow copper traces and see where they go?
You can't really blow the cap in this, even when you short with a screwdriver. The only way to do this would be by exceeding its voltage rating.
The safest way of testing would be with current controlled power supply or with two AA batteries and connect them the way so you can quickly remove one lead, if something goes wrong (unlikely).
Also, can you tell if any of the wires from the capacitor is connected to one of the battery terminals? It should and it would be the opposite polarity to the battery.
If this flash can only be triggered by camera, then it would be done by shorting blue and yellow wires going to the foot but what would be the purpose of this spring contact?
Can you short this spring with pin and try connecting battery (switch in ON position) both ways to see if it starts?
Once we know more we may be able to solve this puzzle.
Last edited by blackchisel97; 08-27-2013 at 06:10 PM.
Actually the flash did fire about every 5-7 seconds. It was great...very little wait time. As for the spring I observed since there is no button as you guessed it was the wall of the case itself that would allow the spring to make contact with the pin and yes the camera mount does have the yellow and blue wire you mentioned. If you google the argus 215 you'll see a couple of sellers with pics that show just how simple the case is and there is no activation button. Only a spring ball at the very bottom of the camera mount. Actually it mount be good to remount that on the case itself for easy of use as an MP. On the back board view you'll see the straight pin connection on upper right of board with the semi circle spring immediately to the left with the larger solder. And yes the cap has both wires going to the board . Remember the green wire was originally black. And if I am right does that mean applying 3 volts only would that still allow it to function albeit weakly or would it show nothing at all??
Ok, so we know one thing, that the spring has to be connected with pin in order for flash to work and blue/yellow wires are for the trigger in the foot (mount). I suspect that this flash operates from 3V (2 AA'a in series) despite both terminals looking the same. What you can try is to short spring contact with pin with an alligator clip or piece of wire and try to connect 3V from AA's in both directions. You should hear the oscillator working, assuming that everything in the circuits is ok. If that works and capacitors starts to charge, red LED should come on after 7seconds. Shorting blue and yellow wires should discharge capacitor by flask bulb.
See if this will work.
I am going to get another flash for immediate use but I am using this as a learning experience. I know now that I have a couple of things wrong...besides what may likely be a burned resistor. I will transfer the guts of this unit to a larger project box and rebuild. I found a decent site that explains how a flash works and it helped point out some things I did wrong ( like getting rid of the trigger plate - I though it was merely a deflector.). Hopefully this will help other newbies like myself.
HowStuffWorks "How Camera Flashes Work".