GH2 GH2 Power - specs, tests, DIY

Svart said:
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.
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Right that's what I'm doing, the cameras stay on (and stay connected) permanently, and I power-cycle the battery which feeds the regulator.

The inductive kick should only be a major problem with fast plug/unplug situations.
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Great, that normally doesn't happen, though with a 10m extension I guess someone could trip over it :).

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.
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I'll look into those, thanks for the advice Svart. So I'd need a scope to measure inductive kicks? I guess a meter is too slow right?
 
Yeah a meter would be much too slow, you'd need a fast storage oscilloscope to catch these transients. I was measuring some the other day in a product I designed with an 8ft dc cable and I was getting 25vdc peaks from a 15vdc. So the transients themselves were 10v above the source and 5ns in duration. I used a snubber circuit and it seems to have fixed it.
 
Svart said:
I was measuring some the other day in a product I designed with an 8ft dc cable and I was getting 25vdc peaks from a 15vdc. So the transients themselves were 10v above the source and 5ns in duration. I used a snubber circuit and it seems to have fixed it.
Click to expand...

Ouch. In my scenario, the regulator would get the kick, not the cameras right? Or does it depend which end of the extension is unplugged?
 
What I measured was at the internal regulators in the device(under full load). This was fed from an 8ft cord (20ga wires), from a 15v SMPS power brick.
 
Really informative thread! I'm picking up a GH2 and will be doing some moving timelapses with it. Once i get my dcc8, i'll be using a 3d printer to create my own battery grip, hopefully with a shutter that will connect to the shutter release port (they have a standard stereo port for shutter release, right?). Once i can measure the gh2 it should be no problem. I've already 3d printed lens cases and hoods, so the tolerances are very tight.

I'll post progress should i go through with it!

pp3dp.jpg
 
alspacka said:
Really informative thread! I'm picking up a GH2 and will be doing some moving timelapses with it. Once i get my dcc8, i'll be using a 3d printer to create my own battery grip, hopefully with a shutter that will connect to the shutter release port (they have a standard stereo port for shutter release, right?). Once i can measure the gh2 it should be no problem. I've already 3d printed lens cases and hoods, so the tolerances are very tight.

I'll post progress should i go through with it!

View attachment 35951
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That 3D printing of the battery grip will be awesome.
The 2.5mm port used for the remote shutter is the same port that is used for an external mic...just so you know.
 
alspacka said:
hopefully with a shutter that will connect to the shutter release port (they have a standard stereo port for shutter release, right?)
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Nope it's not a standard stereo port, the GH's use a 2.5" 4pin socket that shares a stereo mic in with the remote (but the firmware doesn't allow you to use both together). The remote uses just 2 pins (with varying resistances to signify the shutter states). You can buy ultra-cheap remotes on Ebay.
 
I just put together an AC charger using an ac-L10a charger for old sony hi 8 camcorders.
http://cgi.ebay.com/AC-Adapter-Powe...70?pt=Camera_Cables_Cords&hash=item27bb82180a

We have a bunch of them at work that have been retired. The black wire is the positive and the white striped wire is the negative.



I used these tips off of ebay. http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=260616435736&ssPageName=STRK:MEWNX:IT

and the panasonic DMW-DCC8

Really super easy diy. It supplies 8.4 volts or a little more and keeps the camera running in ac mode.
 
Am I correct when I say that with the original DMW-DCC8 in the camera you can have a less strickt powersupply? So there is no need to have a powersupply that is exacly 8.4V but it can also be 12V (and at least 1000mA) and the DMW-DCC8 will regulate to the proper Voltage.

Thanks
 
The voltage has to be above 8.4V for the camera to work. As far as the higher limit, there is no published specifications; 10V might be OK, but it is not clear if the camera electronics is being stressed out or not. The Panasonic AC adapter is just under 9V.
 
"It has been clearly shown (see Thread 3) that the voltage must be above 8.4 volts when the GH2 is powered via the DCC8 adaptor, otherwise it turns off. I"

I'm running my GH1 off a hacked 7.2V (6*1.2V) battery grip that was intended for the Canon 500D. Works well.
When my GH2 arrives and I get a DMW-DCC8 , I'll test that too.
 
Alspacka:
Do you have a design for your grip?
I have a draft for a printable GH1-grip and am working on a conversion kit to change some cheap
chinese Canon 500D grips into something that matches the shape perfectly (gripping the rounded edges)
and can be powered via external 5V USB or power other 5V devices.
(USB cellphone-batteries are so common these days and the Zoom H4n recorder powers fine from USB.)
 
So if we can't power a GH2 from a modified existing 7.2V battery grip, did anyone think about modifying the camera instead of the power supply?
It's not terribly difficult to take apart and re-assemble. (Had to do it with a GH1 already due to some chinese switching the meaning of red and black wires in a battery grip.)
Nothing needed but a household PH0/PH00 screwdriver and a few minutes of patience.
They don't even use terribly many types of bolts in there.
(One could even have a look at lifting the limiation of having EITHER an external microphone or an external shutter release button but not both.)


What if we give it a real battery to talk to but put diodes(to not charge the battery) and an external 7.2V supply onto the + and - contacts?
I have a dead china-battery in the workshop. ;)
 
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@tommyp
Ye, I saw that device as well. I was very curious about using it. I think it'll work just fine as well as be small enough that you can modify to fit inside a camera grip... which could be a nice DIY solution to what the guys are talking about earlier.
 
daihard said:
@tommyp
Ye, I saw that device as well. I was very curious about using it. I think it'll work just fine as well as be small enough that you can modify to fit inside a camera grip... which could be a nice DIY solution to what the guys are talking about earlier.
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It will be totally fine. I use the ubec to power control boards on rc helecopters. They take 5v instead of 9v ubec but it is the same thing. You run your battery to power your motors and then step down whatever else you need with BECs.
 
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