Circuit Diagram?

Does anyone have a link to or know of a circuit diagram of either the 540EZ or 580EX (Mk1) speedlites?

Reason for asking, I was thinking of powering these off camera via a small 6v sealed lead-acid battery with a dummy battery set in the flash, connected via a cable through the battery door.

I have a sneaking suspision that by using the indivdual battery cells, that the internal workings of the flash pull of say 3 volts (by using just 2 cells) for certain aspects of the flashes electronics.

This is just at a thinking off the top of my head stage and I haven't even looked at the price of genuine or grey market batteries but I'm a bit of a DIY'er so I thought it would ask.

Failing this, does anyone know of the wireing of these external packs, (noteing that the external connections of the 580EX has 4 contacts).

Cheers

Mark

I very much doubt the supply will be split off, I wouldn't say there isn't anything in there that would need the split - Unfortunately the only way to find out for sure would be to open her up, or just apply the required voltage to the correct two terminals... This should be absolutely fine even if the supply is split off but then again there are no guarantees I guess.

I have pulled a number of older flashes apart and never found the supply split yet btw...

Thanks. I have just purchased a second hand 540EZ and have downloaded a exploded diagram/parts list, so I may just pull it apart (carefully) and check its innerds.

can't help with circuit diagram, but 540EZ parts catalog here: http://www.f20c.com …ist/SPEEDLITE%2​0540EZ.pdf

*edit* Doh! reads above post carefully...

Mark Vuleta wrote in post #4762267
Thanks. I have just purchased a second hand 540EZ and have downloaded a exploded diagram/parts list, so I may just pull it apart (carefully) and check its innerds.

Just found that thread but the exploded doesn't make it clear does it!

Flashes are usually a pain to pull apart (hidden screws under sticky panels etc.) so tread carefully and again make sure everything goes back 'easily' without any fighting or squashing! You should be absolutely fine! If there is a split I am sure we could sort a little circuit out to suit but I will put my money on there being non!

The main capacitor carries a charge that can KILL!!! If you are not trained to work on electronics, leave your hands in your pockets at all times. (In other words, leave it alone!)

Wilt wrote in post #4764016
The main capacitor carries a charge that can KILL!!! If you are not trained to work on electronics, leave your hands in your pockets at all times. (In other words, leave it alone!)

That is actually a very good point thanks for pointing it out...
I would say that because the main cap is usually placed in the upper half of the flash (along with associated charge circuit), and that the OP should fire the flash at full power and immediately turn off before dismantling but if in the slightest doubt this should be left to someone who knows exactly what they are doing...

Wilt wrote in post #4764016
The main capacitor carries a charge that can KILL!!! If you are not trained to work on electronics, leave your hands in your pockets at all times. (In other words, leave it alone!)

I have an old Vivitar flash. Do you know if it is possible to convert this into use as a TASER? .

A few years I had an old flash that I was stripping apart for the flashtube for another project. The flash hadn't been used for a couple of weeks or so and a piece of shielding bridged the circuit of capacitor while I was taking it apart. Didn't get me, but it let out a crack that reminded to discharge any caps next time.
Used to charge up wire leaded caps in school and toss them to fellow students to catch. It was amusing back then.

Mark_48 wrote in post #4766161
I have an old Vivitar flash. Do you know if it is possible to convert this into use as a TASER? .

Wikipedia says: "The new M-26 Taser models produce a peak current of 18 Amperes in pulses that last for around 10 microseconds.[2]
The internal circuits of most electroshock weapons are fairly simple, based on either an oscillator, resonant circuit, and step-up transformer or a diode-capacitor voltage multiplier to achieve the continuous, direct, or alternating high-voltage discharge. It may be powered by one or more batteries depending on manufacturer and model. The output voltages without external "load" (which would be the target's body) are claimed to be in the range of 50 kV up to 1000 kV, with the most common being in the 200 to 300 kV range. However, since air has a dielectric breakdown (Emax) of 3000 kV/m, it is clear that the spacing of the electrodes will not permit the upper range of claimed voltages (900 kV representing a minimum electrode spacing of about 30 cm). The output current upon contact with the target will depend on various factors such as target's resistance, skin type, moisture, bodily salinity, clothing, the electroshock weapon's internal circuitry, and battery conditions"

From http://hypertextbook.c​om/facts/2004/LukeWork​off.shtml

"A stun gun is a legal electrical self-defense device that puts out a high voltage and low amperage shock. To put things into perspective, one amp will kill a person. Our stun guns deliver 3 to 4 milliamps … However, most stun guns on the market are only 1 to 2 milliamps."

That makes you wonder what the heck the Wikipedia article is referring to, with 18 Amps! Take what you read on Wikipedia with a boulder of salt?!

The civilian version of the TASER has:
Pulse rate: 17 pulses per second (PPS) for 5 seconds
Pulse duration: 100 microseconds
Peak open circuit voltage: 50,000 volts (V)
Peak loaded voltage: 1,200 V
Energy Delivered into load: 0.072 joules per pulse
Current: 0.0021 amperes (A) (2 milliamperes average)

I hope your liability insurance is real good, when you end up tasering someone and throwing them into cardiac arrest, and the relatives come after you with a hostile lawyer!

Looking at the exploded diagram, the 540EZ does not infact have it's charge circuitry in the head, but in the main body. This means that lines connected directly to the capacitor will exist on the main PCB.

(The board inside the flash head is for the trigger, another high-voltage operation but not overly lethal.)


I really recommand firing the flash at full power, then shutting it off *very* quickly. You should then remove the batteries, and let it sit for at least an hour without any powersource before even thinking about opening it.


Flash capacitors hurt. I've had a small, halfways charged cap from a disposable camera fire into my finger, and it wasn't overly pleasant.


Also try to follow the general high-voltage rule: Work with one hand on your back if you are at risk of touching any live contacts. That will at least prevent a path through your heart (the flash will not discharge to ground, and as such only your finger/hand will be torched).

I'm a bit of a DIY'er as well, I don't think I'll be playing around...
Life's too short.. Why try and shorten a little more.

Mark Vuleta wrote in post #4762225
Failing this, does anyone know of the wireing of these external packs, (noteing that the external connections of the 580EX has 4 contacts).

More than likely the external connector on the flash would take in around 200 volts. That is why if you bought and used the Canon CP-E4 external battery pack (about $150US) your recycling time go down dramatically. The external pack contains the circuitry to create the 200 volts from the 8AA's. I have an Olympus 6V external pack for an Olympus T32 flash and it outputs 200 Volts. The schematic for the T32 shows this voltage on the connector.

I don't know how the batteries go into the 580EX, but if it is something like the Vivitar 283 than you should check out this site
http://shutterbug.com …accessories/069​9sb_howto/

Also the flash would use all 4 batteries in series to create 6 volts. That 6 volts would than be used to power the electronics and to create the voltage necessary to charge the main cap.

If you play with the flash circuitry, short the flash capacitor with a 1 meg resistor to bleed off the charge. When you are working in there, use one hand only at first. That way a charge can't go through your heart as easily. There is a guy out there who offers a lead acid pack. I'll try to find the link for you. Why reinvent the wheel?

Chck out www.aljacobs.com

He makes Nicad setups for flashes.

https://photography-on-the.net/forum/showthre​ad.php?t=322674
This is what I was working on for my Sigma Super. I'm sure the concept is very similar. I was actually able to use 9.6 Volts without the flash exploding, but I'm sure it would eventually. A 6V SLA battery is a much better solution, but I was trying to create one that was using NiMH's.