GH2 GH2 Power - specs, tests, DIY

[guyburns]

So it seems even 10V is safe. I tried to connect a DC adapter rated at 9V that displayed 12.5V when open and the camera did not even turn on.

Thanks for the testing, Tyampel.

In general, if the open-circuit voltage of an adaptor is more than about 0.1 volt higher than the rated voltage, that's a clear sign of poor, or no, regulation. Such a supply probably won't be able to jump the 8.4-volt cut-off hurdle of the GH2.

I think it is safe to say that a regulated supply up to 10 volts will drive the GH2 without damaging it. But a lower voltage may mean less current (unless the GH2 is a constant power device), that's why a lower-voltage supply may be better – but not too low. It has to stay away from the 8.4 cut-off.

I would not suggest anyone try higher than 10 volts, especially not unregulated, as there will come a point when your GH2 goes "poooof".

As it stands, Keylight's 780 mA measurement indicates the GH2 is drawing almost twice the power from an external source as from the internal battery. The figure should be confirmed to allow for accurate calculation of run times.

Unfortunately my current meter is maxing out at 200mA so I cannot measure the current going through.

Even the cheapest digital multimeters (well, at least the cheapest I've seen: http://cgi.ebay.com.au/LCD-Digital-..._Equipment&hash=item4cf3b6d92f#ht_3391wt_1141), come with a 10 Amp DC input socket which will be separate from the 200 mA socket. Are you sure your meter doesn't have a 10A socket?

 

[mslade]

So after epic fail with a radio shack 9v 1200mAh supply I got the HQRP supply from Amazon today. Fired the cam right up with my homemade adapter. Marked as 9.5 v 2A but is putting out 9.74v.

Also found an external battery at RS. It works perfect with the adapter, but I don't have a run time yet. Charging it overnight and will test tomorrow to see how long it will last. $32 ain't bad if it will last a while.

Mark

 

[mslade]

Well that RS battery didn't work. New from the store it was 9.23v and it fired up the cam.....but after charging, it was 11.24v and the cam wouldn't turn on. RS has a similar 7.5v battery. I wonder if that will be a higher voltage when charged and work. Might try one when I return this one....

Mark

 

[keylight]

Well that RS battery didn't work. New from the store it was 9.23v and it fired up the cam.....but after charging, it was 11.24v and the cam wouldn't turn on. RS has a similar 7.5v battery. I wonder if that will be a higher voltage when charged and work. Might try one when I return this one....

Mark

Mark,

I'd suggest trying a hobby store if there's one near you. The 8.4v RC car battery has worked flawlessly for me now for a couple of weeks. Seems to me (and I'm not an expert on this stuff, others posting here definitely have more knowledge) that a lower voltage higher amperage battery is a much better solution. Even if that RS battery did work, it was only 1200mAh - it would not have lasted all that long. A battery with a much higher amperage is going to last you a lot longer, and should put out a voltage that doesn't deviate as far from it's rating. A slow decrease in voltage over a long period of time is probably a better approach.... Hopefully others will correct me if I'm wrong on this.

 

[mslade]

I'm sure you are right. I saw it was 9.5 at 1600 and figured it was worth a shot for $32.

Mark

 

[tyampel]

I'm sure you are right. I saw it was 9.5 at 1600 and figured it was worth a shot for $32.

Mark

You are better off with a pack of 8 NiMH batteries. I use the Eneloop ones as they tend to keep their charge when not used. These are rated at 2000mAH.
Amazon is a good source of them. You will need two battery holders from Radio Shack along with some Adaptaplug accessories. The right connector is "C" .

Good luck.

 

[cordvision]

Mark,

I'd suggest trying a hobby store if there's one near you. The 8.4v RC car battery has worked flawlessly for me now for a couple of weeks.

I also have one of these 8.4v RC car batteries. It powers the camera without any problem (homemade battery adapter), but I'm just worried to run it for a longer time because the voltage of the battery when fully charged is over 10 Volts. Does anybody know of anyone who damaged their camera with an 8.4V RC car battery?

 

[keylight]

I also have one of these 8.4v RC car batteries. It powers the camera without any problem (homemade battery adapter), but I'm just worried to run it for a longer time because the voltage of the battery when fully charged is over 10 Volts. Does anybody know of anyone who damaged their camera with an 8.4V RC car battery?

I documented my battery running for just over 8 hours (first post in this thread). I wouldn't be concerned.

BTW, are you metering it at 10v with load from the camera, or without any load?

 

[tyampel]

[
Even the cheapest digital multimeters (well, at least the cheapest I've seen: http://cgi.ebay.com.au/LCD-Digital-..._Equipment&hash=item4cf3b6d92f#ht_3391wt_1141), come with a 10 Amp DC input socket which will be separate from the 200 mA socket. Are you sure your meter doesn't have a 10A socket?[/QUOTE]

Mine is a 20+ years old RadioShack model. But you are right. These multimeters are very cheap these days. I ordered a better one from China for under $10 including shipping.

 

[guyburns]

My imitation GH2 battery has arrived and these are my test results for capacity. Battery rated at 1200 mAh. Capacity determined by discharging at 400 mA until the voltage reached 6.6 volts. Charging was by two methods (as a check on each other):

(1) Using a dedicated charger which began its charging at about 500mA, gradually dropping as the voltage increased, then switching to a constant-voltage charge (8.30 volts) until the current decreased below about 5 mA.

(2) Constant current of 400 mA until 8.40 volts, then constant current at 60 mA (the voltage dropped at this point), terminating when the voltage again reached 8.40.​

The two charging regimes were slightly different, but I didn't expect to see any difference in capacity – and I didn't. Both methods resulted in a fully charged battery.

Results (mAh)
830, 840, 780, 870, 840, 840, 840.

The battery, ~$15 from elect_stores, has about 2/3 of the rating of the official Panasonic battery (yet to be tested). I don't imagine that any other 3rd-party battery would have superior specs at that price point, though I may be wrong.

Still to come: pulling the battery apart to find out what is inside.

3rd-Party DCC8
I have contacted every eBay seller of GH2 batteries suggesting they ask their supplier to manufacture a DCC8 with inbuilt switching regulator ("same as battery, but with no battery, just electronics"). I provided suitable links so they knew what I was talking about. Only one replied, Jimmy from electronic_sell:

Thanks for the information about that item. I have reported it to the factory, if there's any further message, I'll contact me you.

Best Regards
Jimmy​

If anyone sees a 3rd-party DCC8 come up for sale on eBay, please post here.

 

[badpix]

I'll post my notes related to the GH2 battery external power source.
Inspired by the home made dc battery adapters, I decided to make my own out of a block of plexiglas.
After duplicating the battery shape, I drilled two holes straight down for the supply terminals. I bored a slightly larger hole act as a retainer to hold a drop of solder I placed on the end of the wire.
At the bottom opposite the body wire access port I drilled a hole large enough to accomodate both wires and a piece of shrink wrap tubing.
I fed the wires though my holes, snugged up the solder at the top and filed the drops flat. The shrink wrap held the wires in place.

Power Supply
From MicroCenter, I purchased a Velleman "Compact Switching Mode Universal DC power adpater", $49.99
Input: 110 to 240 volts
5 to 24 volt output in 1 volt steps, 4.3 to 1.3 A

I first tried it with 7 volts. Camera responded "Battery not recognized" (or something like that)
Then 8 volts.... camera gave same response.. not recognized
Then 9 volts.... Camera repsonded normally

I shot continuously for 1 hour and 45 minutes using a 30 second exposure with 10 second intervals.

Everything seems to be working fine. Camera was warm, but not as hot as during extended video shooting.

Voltage during shooting remained a constant 9.15 volts
Current at idle (between exposures) 390 ma
Current during 30 second exposure 350 ma
Current during write to SD jumped momentarily to around 410 ma

At the moment, I'll use my APS 110 volt office backup as a power source. I suspect there are some good 12 volt to 9 volt DC converters out there which might be a better solution

Here's what my plexi adapter looks like:
Try this link.. https://files.me.com/badpix/8pwezw

 

[guyburns]

Thanks for detailing you findings, especially the current figures – they confirm Pansonics quoted power consumption of ~3.5 Watts (from the battery). This implies that most of the circuitry of the GH2 probably works under constant power.

If Keylight is reading this, maybe you could edit your first post to include these figures (your figure of 790mA is probably incorrect). I will also edit my posts where I included the higher power figure.

 

[keylight]

Thanks for detailing you findings, especially the current figures – they confirm Pansonics quoted power consumption of ~3.5 Watts (from the battery). This implies that most of the circuitry of the GH2 probably works under constant power.

If Keylight is reading this, maybe you could edit your first post to include these figures (your figure of 790mA is probably incorrect). I will also edit my posts where I included the higher power figure.

Yes, definitely. I've updated first post to include:

Voltage during shooting remained a constant 9.15 volts
Current at idle (between exposures) 390 ma
Current during 30 second exposure 350 ma
Current during write to SD jumped momentarily to around 410 ma

If there are other updates you think would be helpful, let me know. And if you want to write those changes up, I can just quote it into the first post. That would be incredibly helpful.

 

[guyburns]

In case this info isn't already in this thread:

The RadioShack Adaptaplug type "C" is good fit for the DMW-DCC8.
But a better solution is to buy a Sony power adapter for their portable DVD players rated at 9.5 V. The plug fits perfectly and voltage is appropriate as well.​

(from Tyampel in this thread: http://www.dvxuser.com/V6/showthread.php?248127-DMW-DCC8-socket)

And from Brunerww in the same thread:

The plug is 1.7mm inner diameter (ID) and 4.75mm outer diameter (OD) like this one from Amazon. Sadly, it is out of stock, but I also found it here.​

 

[guyburns]

If there are other updates you think would be helpful, let me know. And if you want to write those changes up, I can just quote it into the first post. That would be incredibly helpful.

These threads get unwieldy after a while and need to be summarised when the majority of info is in. In several months time I'll start a new thread (with a link to this one) with a title such as: GH2 DC Power Characteristics /I].

 

[adolgin]

Thanks for detailing you findings, especially the current figures – they confirm Pansonics quoted power consumption of ~3.5 Watts (from the battery). This implies that most of the circuitry of the GH2 probably works under constant power.

If Keylight is reading this, maybe you could edit your first post to include these figures (your figure of 790mA is probably incorrect). I will also edit my posts where I included the higher power figure.

Guyburns, while working on our adapter recently, I looked at the current consumption with a scope (which is much faster than a voltmeter in case not everyone is familiar). The camera indeed draws up to ~.8A in some situations for approx. .5 - .8 sec. I saw it on turn on, and also immediately after using it's own flash. While it does not affect average power consumption, a weak AC power adapter or weak battery would drop their output voltage for that short time and cause the camera to turn off showing the battery message. HTH

 

[guyburns]

The camera indeed draws up to ~.8A in some situations for approx. .5 - .8 sec. I saw it on turn on, and also immediately after using it's own flash. While it does not affect average power consumption, a weak AC power adapter or weak battery would drop their output voltage for that short time and cause the camera to turn off showing the battery message. HTH

That's interesting, a lower inrush current than I was expecting. Since the figure is less than about 1 Amp, that would allow the use of this device: http://products.cui.com/adtemplate_...p=46094&c=194683&catky=&subcatky1=&subcatky2=, a small switching regulator that is a pin-for-pin replacement for the common MC7800 line of linear regulators.

 

[jo447]

I took the time to take a picture of my power setup for the gh2 rig



I use the V-mount plate from TILTA with 5v output for the H4n, 9.3v for the GH2, 12v for my led light
and I still have 2 d-tap output (1 will be used for a monitor)

So far it works, and I'm quite happy.
more than 3hours of camera, light and sound with only 1 battery

Thanks for the forum for the 9.3v value (I guess 8.6v would work as well, and that's probably the value I would choose if I had to order a new plate again, as it's closer to 8.4v)

 

[B3Guy]

Hey, guys! I'm new here on the forum, and I just got a brand new GH2. I'm thinking that for the type of shooting I will be doing, powering off of Tamiya connector R/C batteries would be ideal from a size and weight standpoint. (also, I already have a charger.) What is the recommended setup for this? 8.4v battery, DCC8? What about adding something like this to make battery level monitoring possible?

http://www.alphasportrc.com/index.php?main_page=product_info&cPath=2_27&products_id=1468&language=en

 

[keylight]

I use an 8.4v like you see in the very first post. Timed out at 8 hours. It's small enough to fit in my pocket and give me a whole day of shooting. You'll need a DCC8 or you can make your own of course. That meter looks interesting. I'd probably spend the money on a second battery though.... Good luck. Hope you'll post what you end up making...