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Manzooka
15th November 2012, 09:53 PM
I recently decided to add an Eagletree diversity receiver to my ground station and that leaves me with several more items to power. Previously I was using a 3s 2200mah lipo through the 12v barrel connector on the Fatshark cables. There's an extra 12v barrel connector on the cable that allowed me to power the single receiver I was using as well.

My question is related to the best way to power all of the electronics. Is it as simple as picking up three of the 2.1mm ID barrel connectors from Radio Shack and soldering the three into a single split cable powered directly from the lipo? Also, as seen in the pics, I was thinking of powering the station with that 3S 5000mah I have gathering dust. That should last me ;)

https://dl.dropbox.com/u/551260/Quad/GS02.jpg

https://dl.dropbox.com/u/551260/Quad/GS01.jpg

sl4ppy
16th November 2012, 12:00 AM
Buy (or make) something like this. (daisy chain multiple if you need more outputs)

http://www.readymaderc.com/store/index.php?main_page=product_info&cPath=11_66_68&products_id=537

and a few of these.

http://www.readymaderc.com/store/index.php?main_page=product_info&cPath=11_66_68&products_id=356

I power to receivers and the EagleEyes off a 5000mAh, but be warned, the battery doesn't last as long as you might think. :)

Manzooka
16th November 2012, 12:10 AM
I power to receivers and the EagleEyes off a 5000mAh, but be warned, the battery doesn't last as long as you might think. :)

lol, good to know!

Any significant difference between the solution you posted and using 3 of these cut to length and connected to a single batt connector of my choice? http://www.readymaderc.com/store/index.php?main_page=product_info&cPath=11_66_68&products_id=467

aeryck
16th November 2012, 02:58 PM
lol, good to know!

Any significant difference between the solution you posted and using 3 of these cut to length and connected to a single batt connector of my choice? http://www.readymaderc.com/store/index.php?main_page=product_info&cPath=11_66_68&products_id=467

Better reliability. Using a mass of JST connectors in a harness is just more multiple points of failure for something to come unplugged, especially when considering pan/tilt of the antenna (assuming you ever use the antenna tracking function of EagleEyes).

I'm all for hardwired connections. No chance of pulling apart at the wrong time. As long as your polarity is right and your solder joints are secure, you're golden.

IBCrazy
16th November 2012, 04:03 PM
I use a single wiring harness with multiple outputs with a connector for each device. It's that simple. All you need is a link between your battery and the device you are powering. ON my ground station I use a single 4000mAh 3S Lipo. It lasts me about 7 hours, but I'm not using diversity or tracking.

I agree with aercyk - Hard wire everythnig you can.

-Alex

BldrFlyr
16th November 2012, 05:20 PM
http://www.amazon.com/Female-Male-Power-Splitter-Cable/dp/B004EAMFDC/ref=pd_sim_p_14

I used one of these and taped the connectors together so they won't pull apart.

Manzooka
17th November 2012, 12:23 AM
My thanks for the feedback. I picked up some M connectors from RadioShack and made this tonight. Great solution. Thanks.

https://dl.dropbox.com/u/551260/Quad/powercable.jpg

One additional question... it is okay that I soldered a new video connector onto the stock fatshark cables, rx side? I didn't see any shielding on that cable so I'm assuming just bridging the connections is okay?

I ask because this evening I noticed that the pin on my fatshark vid connector was bent and when I tried to move it into place the pin's metal sleeve broke off. Oops. I had some spare video cables so I cut off the fatshark connector and soldered a new one in it's place. Seemed simple enough, one insulated center wire and the outer wire. I made the connections and insulted the inner wire with a little electrical tape before shrink wrapping. It definitely works, so I guess my question is whether or not this could any unforeseen (by me) transmission troubles?

Scotttu
17th November 2012, 12:59 AM
Terminal block?

I used one for a while but as I powered things separately I went with separate batteries but now I"m ready to go back to this:

http://www.marathonsp.com/DoubleRow.html


http://www.marathonsp.com/Images/200.jpg

Manzooka
17th November 2012, 07:52 PM
Okay, my last question was clearly a non-issue... at least within a mile. Great flights today with the exception of GoPro jello I still need to work out.

Carbon
15th January 2013, 09:37 PM
Ok, simple question. If I was to power a basic 12v fpv system of a 200mw 5.8ghz tx and a Sony 600tvl camera off of a single 3 cell lipo, how many mah are necessary for a continuous run time of say 1 hour?

aeryck
15th January 2013, 09:48 PM
Look up the specs of each component, specifically current consumption, add them all up, and as a safety margin multiply by 1.2.

Example: camera 150mA, vtx 500mA, add them up to get 650mA, then multiply by 1.2 and get 780mA, so let's call it an 800mAh battery for 1 hour of use with a bit of room for error (and to prevent fully discharging, which is a bad thing).

AustinFPV
15th January 2013, 09:49 PM
Wondering the same and posted on the other forum. I just ordered a 370 mA from HK since everyone seems to be out of stock on these small batteries here including HKUSA. RMRC includes 450s with there packages. Interested in any replies.

http://www.rcgroups.com/forums/showthread.php?t=1808397

Carbon
15th January 2013, 09:53 PM
Yeah, I would have done that aeryck, but there were no specs so I was wondering what is a standard.

Vintabilly_NS
16th January 2013, 07:22 AM
You can take those numbers and use them. If they're off it's not by much. :)

Vintabilly_NS
16th January 2013, 07:23 AM
or go with a 1,000mah pack and don't worry unless it's a weight issue.

~Jer.

EDIT: sc2000 says 120-140mA for the pz0420

Ace4
16th January 2013, 12:00 PM
Ok, simple question. If I was to power a basic 12v fpv system of a 200mw 5.8ghz tx and a Sony 600tvl camera off of a single 3 cell lipo, how many mah are necessary for a continuous run time of say 1 hour?
I use the PZ0420 camera (also have an OSD) and same VTx with a 3s450mAh LiPo. After a 20 minute flight, it's usually around 3.9V per cell, so I would estimate I'm using 13-15 mAh/min. For a full hour you'd probably want 900-1100mAh pack for a safety margin.

Vitamin J
16th January 2013, 12:52 PM
Carbon, why don't you run the video gear from the flight battery? Much more reliable because you don't have to worry about the vid battery going dead mid-air ;)

airbagit13
16th January 2013, 12:59 PM
I personally use a 460 mah 3s lipo for my flights. I used to use an 800 still do sometimes but I have found 460 to work nicely.

Outdoorz
17th January 2013, 06:15 PM
Carbon, why don't you run the video gear from the flight battery? Much more reliable because you don't have to worry about the vid battery going dead mid-air ;)

Agreed

Outdoorz
17th January 2013, 06:21 PM
So earlier today I was surfing youtube just looking at awesome FPV flights and stumbled over a video that made a lot of sence to me. The guy was using a lawn mower battery to power his ground station. In the description he added that he only charges it once a month and flies frequently. Has anybody seen this or know exactly what things are needed to make it work? Maybe even know what video it was, because I can't seem to find it again:/

ProtoCrash
17th January 2013, 06:56 PM
I used to use a motorcycle 12v batt. Yes it lasts forever but weighs an absolute ton... Im now back to nice and light lipos! I dont think its worth the weight at all to be honest.

ProtoCrash
17th January 2013, 06:59 PM
I use a 1300 batt and it powers fpv gear plus rx and servos. Logic is that if my flight batt dies i can still glide and if worse comes to worse i can still pick up video signal for a couple of hours. A 20 min flight gets it to around 80percent...

chanyote66
17th January 2013, 07:00 PM
I use a 2650 Transmitter Lipo... Super light and Efficient... Lasts a good week of flying and only takes 20 min to charge... I got a Lipo procector circuit from batterysplus so it charges from any 12-14v source and does not allow the Battery to over discharge.

Chris

chanyote66
17th January 2013, 07:05 PM
For my Flights I use a 2200mah 3s for video equipment... and 10,000mah 4s for Motor and Plane equipment...

Video equipment...

2x PZ0420's
1x 1000mw 1.2ghz VTX
1x DOSDv2
1x Video switch

On a 1 hour flight I used about 1100mah of the 3s and 4800mah of the 4s

It all depends on the size of your plane

Chris

Dust
17th January 2013, 07:06 PM
So if my TBS tuned 2G4 Vtx is rated for 450mA, (but no mention of the hour in mA"H") That is still rated per hour, right? Id been meaning to ask but didnt want to start a new thread for it, so im glad this one popped up.
Also I have no idea how much my Rx and all its servos will take. I cant even speculate how much mAH would be needed. (FUTL0831 Futaba 8ch 50Mhz Rx, with 6 HS-55 (flaps, ail, rud, ele), 1 HXT-9 (tilt), and 1 HS-65mg (pan) servo)
I have planned a 3 cell 1300 mAH for my Motor and TBS69, and a separate 2 cell 800 mAH for Rx, Servos, and the above mentioned Vtx.

Forgot to mention that I am testing it all out in a Calypso glider

chanyote66
17th January 2013, 07:08 PM
I usually give an extra 10% over for the estimated power required by the VTX...

1000ma output = ~1100mah used power

Carbon
17th January 2013, 07:08 PM
I decided to go with the flight battery. Thanks for the help dudes!

ProtoCrash
17th January 2013, 07:10 PM
By the way, best way is to test fly for 5 mins line of site and measure how the battery... Then you know how much youve drawn

Dust
17th January 2013, 07:14 PM
By the way, best way is to test fly for 5 mins line of site and measure how the battery... Then you know how much youve drawn

Thats exactly what i was thinking. Measure exact mAH before flight, fly for a few minutes with plenty of stick moments and use alot of my servos, land and remeasure. Extrapolate out and get the idea.

SecretSpy711
17th January 2013, 07:19 PM
Currently I use a 5000mAh hardcase LiPo that was originally intended for something else. Lasts quite a while, and if I ever forget to charge it I can just grab another batt I have lying around because I have the same connector on all my batteries.

Lead-acid is pretty old tech, but if you use one (like a motorcycle batt as Proto suggested, or there are smaller ones), then just put it in the back of your car hooked up in parallel with your car battery and drive around with it. This will automatically keep it charged and you will always have it with you.

Hmerly
17th January 2013, 07:23 PM
Old lead acid batts are nice but too heavy. Just use a nice 3s lipo and you should be good to go. Much simpler and a whole lot lighter.

UH60MPilot
17th January 2013, 07:24 PM
Yeah, I've got some of the kids 12v power wheels batteries that would probably last a long time as well

AustinFPV
18th January 2013, 01:14 AM
I usually give an extra 10% over for the estimated power required by the VTX...

1000ma output = ~1100mah used power

Don't you mean 1000mW or 1 Watt? At 12 Volts that should be 83mA for the VTX plus some since its not 100% efficient. P=V*I or in this case 1W=12V * .083A.

This is why I went with the 370mA battery. At 80% I should be able to pull 300mA out of it. Using just a 800mW VTX and Cam of unknown current consumption I'll guess high at 150mA which should give me 2 hours of power. What am I missing here?

ProtoCrash
18th January 2013, 04:20 AM
I suspect efficiency of vtxs may be much worse than 90pc... Weve all seen how much heat they produce.

Hucker
18th January 2013, 05:21 AM
Why don't you measure your current draw with a meter?

Or fully charge your battery, run your system for an hour (with a fan on vtx) and recharge your battery. Then just read the mAh off the charger. That way you will know your system.

All that said single battery is the way to go.
Sent from my Windows Phone 8X by HTC using Board Express

IBCrazy
18th January 2013, 10:25 AM
I use a 4000 mAh 3S because it fits in a pocket of my satchel system nicely. It is very much overkill. For my other stations, I use old worn out 2200mAh Lipos.

-Alex

RcLab1
18th January 2013, 10:29 AM
3s-5000mah Lipo,
How long ~will it last~ powering these 4 items on my GroundStation?:

RMRC 8" monitor,
Pyle Video Splitter,
FatShark Base2012 goggle, and
RMRC 1.2ghz VidRX.

Will I be good (fly safely with enough left over) for a couple hours?

Keok
18th January 2013, 10:45 AM
I use a battery from a computer UPS battery back up. Its a little heavy but I needed the weight to counter balance 19 inch LCD in the lid of the case. I haven't had to charge it yet its been over a month. But when I do I'll just put it back in the original case over night.

aeryck
18th January 2013, 10:51 AM
3s-5000mah Lipo,
How long ~will it last~ powering these 4 items on my GroundStation?:

RMRC 8" monitor,
Pyle Video Splitter,
FatShark Base2012 goggle, and
RMRC 1.2ghz VidRX.

Will I be good (fly safely with enough left over) for a couple hours?

More than likely you'll be fine.

One way to tell is if you can look up the electrical specs of each device on your ground station, specifically looking for the current consumption in mA, and add those values up. Or, if you have an inline wattmeter or a multimeter that can read amp draw, you can hook up your ground station with the current meter inline, and record the total current draw of the whole system while it's powered up.

Once you have your current draw, it's a simple matter of dividing the capacity of your battery pack by the total current draw, and that will tell you approximately how many hours the battery will power the device. Remember, it's always best to give yourself a margin of error, both for inconsistencies with battery's actual capacity and also to prevent fully discharging the lipo.

Let's say your monitor draws 300mA, your video splitter draws 100mA, the goggles draw 250mA, and the vRx draws 150mA. If you add all these up, you get a total current draw of 800mA. Divide the battery capacity by the current draw, or 5000mAh / 800mA, and you're left with approx. 6.25H, or 6 hours 15 minutes.

Now, let's add an 80% safety margin - multiply your duration by 0.8 (80%) and you get 5 hours of safe run time before the battery needs to be recharged.

Make sense?

Edit:

The values I used in my example above are NOT actual values! They are for example purposes to show you how the math works out. Do not rely on my values for your battery's run time - Either use a current meter or look up the actual rated current draws of each device for the most accurate results. =]

SENTRY
18th January 2013, 11:10 AM
merged with pre-existing thread

SENTRY
18th January 2013, 11:20 AM
merged the 3rd thread w/ the other 2.

viper522
18th January 2013, 12:32 PM
Since I typically fly 'from the trunk' and require an inverter for my camcorder, I use the car's battery thru the cig lighter socket in the hatch. A string of JST connectors powers the small LCD, Fatsharks, video splitter, anything else i might need there. If you do this make sure there's a fuse between your car battery and your gear! Since the inverter is already there, I run an extension cord out to the VRX and power it with a transformer. A nice option is that I can run a household fan in the hotter months too. And I can be confident that I never need to charge the car battery because if it started the car and drove to my spot, it's fine, and will recharge whatever I've used on the drive home.

I'll no doubt change this setup as I get bored of local FPV and decide to get away from places with vehicle access. Of course I can cut it down to just VRX/goggles/lipo in a bag at any time and fly that way too.

chanyote66
18th January 2013, 12:40 PM
I use that same Phillips screen... This is my GS before the 2650 was installed inside with the charge/protection board

1968119682


http://www.youtube.com/watch?v=x9gCNv9vk-o


http://www.youtube.com/watch?v=TiwhrHxnoSU

rawlmark
18th January 2013, 01:43 PM
I use that same Phillips screen... This is my GS before the 2650 was installed inside with the charge/protection board

1968119682



Simple & functional, very nice!!

chanyote66
18th January 2013, 02:02 PM
Simple & functional, very nice!!

yup... Plug in power and it starts recording... less buttons and crap... more flying :)

Outdoorz
18th January 2013, 02:17 PM
I use a battery from a computer UPS battery back up. Its a little heavy but I needed the weight to counter balance 19 inch LCD in the lid of the case. I haven't had to charge it yet its been over a month. But when I do I'll just put it back in the original case over night.

Kinda off topic but what 19inch tv are you using? I am currently trying to find one that is 12v and the blue screen of death is minimal.