Some Good Deal on Amazon Batteries

Need some rechargables AA and AAA batteries?  These seem to be a good deal.  The Internet believes they're manufactured by Sanyo and are rebranded Enerloops.  Woo hoo!

AA 2000 mAh
AA 2400 mAh
AAA 850 mAh






And two chargers:

EBL 808 8 bay charger
EBL 807 4 bay charger



blogodex = {"idx" : ["power", "batteries"]};

LiFe battery in a 4x2x2 battery compartment

 Somebody on RCGroups was asking about how LiFe batteries fit into receivers with a 4x2x2 battery compartment, similar to what's on a Turnigy 9x.  Here's some pictures of how it fits (summary: just right!).  There's no stress on the battery compartment cover when snapping it on, and just enough room for the wires.  Use the power connector that looks like a servo connector.


HobbyKing 1500mAH LiFe 3S 9.9v Transmitter pack

It fits nicely in this configuration, but the 9x power connector is blocked.  This may or may not affect you depending on your receiver's connector configuration.

3.3V PSU Update

I've configured the PSU I got a while back.  This is needed for the  5.8GHz video transmitter from Range Video.

It was pretty straightforward to assemble.  I put a JST connector on the input and output, desoldered the 12V pad, and soldered the 3.3V pad.  I wrapped the whole thing in a 3/4'' shrinktube, but a 1/2'' would have been better.

I'm not sure what the signal line is for.

Step Down PSU, 3.3v, 5v, 9v, 12v

Ordered this from hobbyic.com and stashing the docs, such as they are, here.  They note: "Do not power 1W video transmitter"

eCalc propCalc -- Propeller Calculator!

Courtesy of the most awesome brosius85, here's a great power system calculator that seems pretty comprehensive.  It has a large selection of motor data, nice charts showing the power curve, and warnings when some parameter is out of whack.  Thanks Brosius!!

Arcticopter IV power loading

    battery  amps watts     notes
3S 2200 15c    .5     6     powered on, no props
              3.2    36     armed, motors at lowest speed
             16.0   184     half throttle
             33.3   313     full throttle (15c)
3S 2200 40c  39.3   413     full throttle (40c)


motors: hacker Style Brushless Outrunner 20-22L x 4
ESC:    Turnigy Plush 18A x 4
props:  10x (3.8?? 4.7?? I will check later...)

12V DC power stepup module

Input DC 3.5V~10V, output 12V, 1.5A (2.5A max), 26Watt
$5.75, listed here on bay from vendor coldfusionx.

Using XT60's for power distribution

dalswede on rcgroups has a nice post on his quad.  Here's his XT60-based power distribution unit, future-proofed as he notes for a hex.

WAGO 222-415 connector for power distribution

Here's a nice flickr set by Lenz Grimmer for his quad build.  He is distributing power using Wago connectors and credits Christof Glückler for the idea.  Genius!!

The 5-connection unit is WAGO 222-415.  They also sell 2 and 3 connection units.  There's a couple of people selling them on ebay.

Power Guidelines

Courtesy of PhilipA on RCGroups:

• 50 watts/lb: Minimum required for flight.
• 70-90 watts/lb: Trainer and slow flying aerobatic models.
• 90-110 watts/lb: Sport aerobatic and fast flying scale models.
•  110-130 watts/lb: advanced aerobatic and high speed models

He notes:

• 80-100w/lb nice target for many planes.
• The Blue Wonder maxes out around 85 watts on a 3S lipo and GWS 9x5HD (straight blade) prop. 
• Sufficient for up to a 16oz AUW plane with decent performance including a 4ch aileron version.