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    I figured as much with regards to the disposables. The rechargeable lith I'll focus on. But the alks was an after thought if I'm in a pinch for power.
    The GH2 stops round 7v, so 3-4 in parallel should give you at least 45m off the disposables. (Fingers crossed)
    Reason I'm interested in 9v is because the Cells could fit in a battery grip quite easily.
    Last edited by daihard; 05-31-2011 at 09:17 AM.


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    Quote Originally Posted by daihard View Post
    I figured as much with regards to the disposables. The rechargeable lith I'll focus on. But the alks was an after thought if I'm in a pinch for power.
    The GH2 stops round 7v, so 3-4 in parallel should give you at least 45m off the disposables. (Fingers crossed)
    Reason I'm interested in 9v is because the Cells could fit in a battery grip quite easily.
    For an external power the GH2 will stop at 8.37v. So with 9v batteries you will not utilize their full potential.


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    Senior Member monkeyking's Avatar
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    AC Supply001.jpgSo is it safe to run my GH2 on a GH1 charger/power supply via DCC-8 ?
    Last edited by monkeyking; 06-06-2011 at 10:59 AM. Reason: photos added


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    And here it is...
    Senior Member keylight's Avatar
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    Got my DMW-DCC8 today. Very cheaply made. No cutting required. It opened using my hands. Just popped apart. Sad that it took so long for Panasonic to mass produce these....

    And it is pretty much what we thought. Just two contacts used.

    DMW-DCC8-open.jpg

    DMW-DCC8-board-front.jpg

    DMW-DCC8-board-back.jpg

    Looks like they are using these resistors:

    http://uk.digikey.com/1/1/4481613-re...12zyj102u.html

    ERJ-12ZYJ102U.JPG

    digikey.jpg
    Last edited by keylight; 06-01-2011 at 01:52 PM.


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    Interesting that they have a 2Kohm load on that board. Must need it for power supply stability or something.

    I took the 10$ ebay battery I bought and disassembled and then gutted it. I removed everything off the PCB but a tantalum cap and reverse protection diode and soldered a lead/connector, just like that one in the pic, to the PCB and ran it out the bottom corner of the battery case.

    It works great. I just hacked a small 5v switcher into a 8.5v output to use with it too.


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    And based on the size of the resistor compared to the size of the wire lead, those look more like 1206 parts rather than 2010 parts.


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    Senior Member g.l's Avatar
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    To follow up my last post, I tried my 3m DC extension cable again @ 8.6V, and today it worked. But the 10m extension needed 9.05V (unloaded).

    When measured, the extensions droop briefly during the intial power-up, but quickly stabilise (but the camera has already seen the dip and rejects it).

    Electronics gurus, what is the cause? Resistance of the cable? (the 10m measures about 1.5ohm) And what's the correct way to address this? More voltage works (and I guess 9.05V is safe), but would (say) a larger output cap after the regulator work instead?
    Last edited by g.l; 06-06-2011 at 10:31 AM.


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    resistance yes, but might also be inductive/reactive. Since your power source is at one end of the cable and the load is at another end, the source sees a resistive and inductive path before having to charge the capacitors on the input of the camera while simultaneously needing to source all of the power the camera demands at once. This can cause a lag in time between where the camera demands a lot of power and where the switcher senses it's outputs drooping and increases output(propagation delay). Thicker wires can mitigate this when using long cables. Be careful though, long cables between the powersupply and unit can cause a condition where you get an inductive kick when making/breaking the circuit when it's under load(not turning off camera first, accidentally kicking out cord, etc). I would use the shorter DC cable and use a longer AC extension to the external supply.


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    Quote Originally Posted by Svart View Post
    resistance yes, but might also be inductive/reactive.
    How could I measure this? I only have a multimeter, but I really should get a scope.

    Since your power source is at one end of the cable and the load is at another end, the source sees a resistive and inductive path before having to charge the capacitors on the input of the camera while simultaneously needing to source all of the power the camera demands at once.
    I see.

    Be careful though, long cables between the powersupply and unit can cause a condition where you get an inductive kick when making/breaking the circuit when it's under load(not turning off camera first, accidentally kicking out cord, etc). I would use the shorter DC cable and use a longer AC extension to the external supply.
    This one worries me. I'm powering both cameras from the same regulator - it's a 3D setup (2 bodies), and both must be turned on at the same time, so that their clocks are reasonably in sync (required for frame sync, which is important in 3D). That only works if the cameras are already switched on before you power them, and they regularly need to be power cycled this way (as the clocks gradually drift).

    Usually both bodies are within 1 meter of each other, but for some very distant shots I need to separate them much more to heighten the depth effect. That's why I will occasionally use a 10m extension cable for one camera, and they have to be on the power line (after my regulator). So I really need to check on any inductive kick, and some way to mitigate if it's a problem. Any ideas? The TI regulator has a 'soft start' (slowly ramping voltage up), will this help mitigate the issue at powerup?

    Actually thinking about it, this could presumably also affect the power-up timing of the camera on the extension, that could be bad.
    Last edited by g.l; 06-06-2011 at 12:09 PM.


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    The "softstart" function only works when the switching regulator is powering up, not the cameras. If you plug the cameras in first and then turn on the power to them, you should be OK. If the cameras are off before you unplug them I wouldn't worry.

    The inductive kick should only be a major problem with fast plug/unplug situations. Using a snubber circuit, a TVS or simply a reverse biased zener(maybe 10v or so) should clip off the transients enough to not be a problem.

    http://www.coilgun.info/theoryinduct...vekickback.htm
    http://en.wikipedia.org/wiki/Inductive_kick


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