How to replace 4 AA's with a 6V battery

[lawdog]

At one time on the site I saw where someone had rigged up fake batteries made from dowel rods to replace AA's and run them from larger batteries. I think they were doing this for an Owl.

I want to do the same for a Digi Slave Flash unsing a 6V battery in place of 4 AA's. Is the dowel rod thing the best way? If so can anyone point me to where that was illustrated?

Is there a better way?

Thanks

 

[Tinhorn]

Howdy,

That was Archy's design for the Fake Batteries, I'd think it'd work in your case too!

http://archilochus.netfirms.com/

Tinhorn

 

[lawdog]

That is what I was looking for - Thanks.

 

[lawdog]

I have seen all of the data on how to run 1.5v batteries in parallel to make the battery run twice as long but still produce 1.5 v's. I've seen the data on how to run 1.5v batteries in a series and make them produce 3.0 v's.

But how do I take a 6v battery and run it to a flash that takes 4 1.5v batteries (and has 4 seperate posts for batteries)?

Any ideas?

 

[GeorgiaHunter]

Typicall devices such as flashes use the batteries in series you need to open it up and measure across the leads going to the circuit board. I am thinking you will find 6V and can connect directly to the lantern batt.

 

[shrtcirkt]

Be careful running a larger battery on your flash units. Not too long ago we started playing with external batteries on our DS20's and Q15's. We found (Arch may remember this) That the flash has the capability to draw large amounts of current when charging. This extra current smoked the components on the circuit board pretty quickly.
I've finally gotten a current limiting device to try out and hopefully will get it connected to a flash in the next few days to try out.

 

[lawdog]

Here is a basic question:

If the flash has 4 posts where 4 AA batteries go can I take a 6V battery with 2 Alligator clips (pos & neg) and clip those to two of the posts (pos & neg)? This would obviously leave two of the posts in the flash with nothing attached.

 

[Archilochus]

Yes you can - make sure to get the right posts and do not reverse polarity by accident. But go up a few and re-check the post from shrtcirkt - you might fry your flash! The small 'AA' batteries have an internal resistance that increases with load - this self-limits the current that can flow while the flash charges. Connecting batteries that can deliver more current (lower internal resistance) can cause an over-load of the flash charge circuit. You should be OK with 'C' cells - but that's just a guess.

 

[Tinhorn]

The Surge Protection design utilizing a smaller battery size is interesting, I've never heard that before. I know one thing for sure, making a mistake with high amp batteries is more "Interesting" than smaller amperage ones, all that current will literally burn up things real quick.....

Tinhorn

 

[Jon5ja]

I don't know about the DigiSlave flashes, but have noticed on the inexpensive Vivitar flash units that just replacing the alkaline batteries with NiMH cells considerably increases the peak current draw when you first turn on the unit. No burnout problems yet, but the 2SC3420 in it can handle 5 amps continuous, 8 amps pulse.

From Eveready's site, looks like their alkaline AA cells have an internal resistance of about 0.145 ohms per cell (new). If the flash was designed to work with 4 alkaline cells, I think it'd be safe to add a 0.5 ohm, 5-watt resistor in series and run it off any 6-volt supply, IMHO.

Jon