Safe use of older flash guns

Does anyone know where on the web one can find a guide to which older flash guns have a safe trip voltage suitable for use with Pentax DSLR models.

Thank you for any help in this.

Just measure the voltage across the terminals with a voltmeter.

I believe all Pentax flashguns are under 10 volts.

Basically, if it's a make you've heard of, and it's less than fifteen years old, you have nothing to fear.

And even if it isn't, you'll probably be all right.

G

Be cautious with older 1970s flash guuns, some of which have trigger voltages approaching 300V. Idential looking Vivitar 283's for example can vary from 28V to 290V, so obviously there were different versions made.

The only safe thing to do is to measure the voltage with a meter.

George, thank you for your reply....

I did think of putting my meter across the sync plug but assumed that the short flash duration would not allow the meter needle to deflect properly/fully (although come to think of it I have a digital meter now as well) The gun is a Sunpak Auto-zoom 3600 and it must be about 20 years old now I should think.

I did spend quite a long time this evening looking for a site which has a list but can't find it now....

John,...thank you for your reply. I do have a Vivitar 283 (about 33 years old) and know about it's high voltage whic is why i'm being careful with the Sunpak.

Not all modern flashguns have safe trigger voltages (though apparently most dedicated ones do). I have a very small Jessops flashgun bought about 3 years ago which has a trigger voltage of 300V.

Jonathan

The Pentax AF400T is 100V, it is marked on the 'rating plate' and the DS hasn't melted yet.

I too have an older flash. Where would I need to meter ? ( I did ask once before, but haven't got around to doing anything about it yet ).

Would I need to put the flash on my Super ME hotshoe, then meter the link wire whilst the flash triggered?

Although the flash I have isn't ideal, I can't afford one of these "posh" ones, but it is a way of conserving battery power in the camera.

You get your voltmeter, place the two contacts on the flash hotshoe contacts and fire a test flash. Try it a few times until you are happy that you have a reliable result.

Mmm, I did this. Well similar. There is no test button on the flash ( it is a VERY old "National PE-145" ). I connected it to my ME via the lead, and put my meter on the shoe terminals, then "clicked".
There was no voltage registered on the terminals. Is that because I was using the lead?

I suppose the next step is to open the flash up, put it on the hotshoe, and meter the terminals from inside when I trigger it.

It isn't a fancy adjustable flash, but all I'm planning to use it for is to conserve the battery power in my camera.

I'll put a "proper" flash on my Christmas wish list

You can try this site but i am not sure how reliable it is.

http://www.botzilla.com/photo/strobeVolts.html

DO NOT open up the flash, it will hurt

Leave the flash off the camera and switched off, set the multi-meter to measure VDC. Put the leads for your meter onto the central contact on the flash (+ve lead) and the "earth" contact on the side of the hotshoe mounting on the flash (-ve lead), make sure you are NOT touching the tips of the leads, and turn on the flashgun. You will see the voltage climbing quite rapidly initially as the capacitors inside charge up. You should not have the flash mounted on the camera for doing this measurement. There is no need to fire a test pop on the flash.

I gave up measuring as my old National PE-[some number I can't remember] went past 300V DC. This kind of voltage will really hurt you if you touch it.

Duncan

I can certainly testify to the pain. I couldn't believe the shock that I got from a tiny Optio and my fingers were nowhere near the capacitor which, incidentally, is the biggest component in the camera being the entire height. I had to dismantle an AF400T to sort a broken wire, boy was I careful.

Thanks.

I've had capacitor "zaps" in the past. Also had some really nasty shocks from car ignition high tension leads, back EMF from relays dropping out oh..and thrown across a couple of kitchens with mains shocks.

Sort of used to it now

But thanks for the heads up! I'll do the test your way, but it sounds like you've already established the voltage is too high

Safe trigger voltages have been discussed before here -

https://www.pentaxuser.com/forum/viewtopic.php?t=6750&start=0&postdays=0...

and the web site you require is mentioned in one of the posts.

Good luck.

Howard

Jessops is not a make I have ever heard of. In fact, it's not a make at all. It's often cheap Chinese rubbish.

To be more sepecific, I meant flashguns made by established photo manufacturers.

G