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Old 8th January 2008
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Wreckdiver Wreckdiver is offline
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Re: HLD-4 power grip

Quote:
Originally Posted by Melaka View Post
Thanks for the lesson Steve. How does one know which battery the grip is using? Does it use a fully charged one first or a partially charged one? I get the theory about the CR123s but they total 9v which is a lot more than 7.2v even if a diode gets in the way.
I can't be 100% sure as I don't have my HLD-4 yet (Olympus - I'm still waiting), but they will almost certainly be used simultaneously (in parallel). So the batteries will be discharged equally until both are flat. To use one until flat and then use the other wouldn't make any sense as extra electronics would be needed to monitor the voltage levels and provide switching. A couple of cheap diodes is the simple, reliable way to do it.

I haven't used CR123s and didn't realise what their voltage was, but your question is very valid, there shouldn't be any problem with a 9v supply. That is puzzling, I thought that some people may have been having problems with two BLM-1s in the holder, but if it is with just CR123s then it doesn't add up. The only way to check conclusively is to to dismantle an HLD-4, load it with CR123s and measure the terminal voltages on the workbench to see what is going on inside it.

When I get my battery grip from Oly I would be interested in having a play - these things intrigue me. So maybe I can find the answer then. Unless of course Olympus want to comment on the problem.

Watch this space.

Steve
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