Sunday, March 1, 2015

Recording Taranis Audio Files

Here's some notes on recording Taranis Audio Files.  It assumes you can (a) download and install software on your computer and (b) see your Taranis SD card.

  • Project Rate (Hz): 32000
  • Audio Track: Mono
  • Sample Format: 16-bit PCM
  • Export Format: WAV (Microsoft) Signed 16-bit PCM
  • Audacity -- Open source, multi-platform recording software.
  • CleanMyDrive - (Mac) Cleans junk files when disk is ejected.  Use this to get rid of the extra files the Mac Finder puts on the SD card.  Some of the filenames are too long and confuse the Taranis.
SD Card Location
  • User sounds go in /SOUNDS/en
  • System sounds go in /SOUNDS/en/system
  • The SD card will show up in the Finder (Mac) or on the Explorer (Windows).
  • If you're on Linux i'm sure you already know how to find it. :)
  • "en" is for English.  I think there's corresponding folders for different languages.

blogodex = {"toc" : "Taranis", "idx" : "audio recording"};

Tuesday, February 24, 2015

WLToys V686G Mini FPV Quadcopter


Here's some notes on my review of the WLToys V686G Mini FPV Quadcopter. It was sent to me free of charge for review by GearBest.

The unit is available here:
I don't get any money for this, but there's has a coupon code GBV686G.

Executive Summary

  • It's a good flyer and I think it will be pretty popular.
  • Video is pretty decent for the price.
  • Lights are great...  this unit looks good at night.
  • Buy some extra batteries and a charger if you don't have one already.
  • The manual is pretty terrible.  But I'll summarize everything you need below!
  • Constant Tx beeping in heading-hold mode is crazy annoying!
  • Doesn't seem to state video channel.

In the Box
  • Quadcopter, Transmitter, 1S 780mAh Lipo Battery
  • HD Camera, Video Monitor, Video Antenna, 4GB Micro SD card, USB Card Reader
  • 4 spare props, 4 prop protectors, Screwdriver, Monitor mounting hardware, Manual.
  • LiPo and Monitor chargers, manual
Note that the web page advertises a 2GB Micro SD card, but mine came with a 4GB card.

Battery Spec

  • 1S,  780 mAh, JST connector, no specification on C-rating but I'm guessing it's 25C
  • Transmitter takes 6 AA batteries (not included).

Setting Up

Setup is easy.

  • Charge the LiPo battery and Video Receiver.  Put AA's into the Transmitter.
  • Attach the Video Receiver to the Transmitter with the supplied hardware.
  • Put the quadcopter on a flat surface and plug in the battery.  The light will start to flash.
  • Turn on the Transmitter.  After a few seconds, the quadcopter light will go solid and the Tx will stop beeping.
  • Put the battery into the bottom of the compartment. The wires will fit nicely into the top.
  • Ready to Fly!


The stick controls are standard.  Special controls are:
  • Left shoulder button : video record on/off.  The blue camera light blinks while recording.
  • Right shoulder button: Flip mode. Click, hear fast beep, move right stick in direction of flip.
  • Button 1,2,3,4:  Rates: 40%, 60%, 80%, 100%
  • Button 5:  Lights on/off
  • Button 6:  Camera, still picture
  • Button 6 (2 second press) enter/exit headless mode


Headless Mode
Normal Flight
FPV Flight
Night Flight


Monday, February 16, 2015

Notes onOneShot 125 ESC Communications

Executive summary:
  • uses a pulse with of 125-250 usec, rather than the typical 1000-2000 usec.
  • sends a pulse ("oneshot") once per execution of the flight controller main loop.

At the time of writing, Flyduino KISS ESCs and Naze boards support the protocol

Cleanflight notes. Originally put into BLHeli(?). Nice video explanation.

blogodex = {"toc" : "OneShot"};

Friday, February 13, 2015

Fixing UMX Radian Porpoising

BrownShoe at RCGroups posted a note about eliminating porpoising on his UMX Radian.

After I established the CG at 32 mm, I cranked in some negative elevator with my needle-nosed pliers; the little U-bend was almost closed. She flew kind of crazy. It was way too much negative elevator and the wind was very choppy and I came close to crashing. What I noticed was, it did not porpoise! Ha! I landed and opened up the U-bend some and tried again. She flew with nary a dip! It was the nicest flight she has ever flown!  
I performed a dive test as best I could while trying to remember what to look for. It had a nice gentle rise and not an abrupt porpoise. Nice! I flew three packs and she handled very well in spite of the very choppy air. I let it glide hands free for a good ten seconds. Finally it flies like it is supposed to and I'm having maximum joy now. 

blogodex = {"toc" : "UMX Radian", "idx" : "porpoising"};

Tuesday, February 10, 2015

Concord Model Engineers Minutes, February 2015


Tuesday, Feb 10, 2015

CALL TO ORDER:  7:30 pm


Monthly meeting, Second Tuesday, 7:30 at Concord Airport Terminal.

Friday Fun Fly, Third Friday, 7:00 - 9:00 pm.
Gym at the Church of the Nazarene, 1650 Ashby Dr., Concord

Fun Fly this month on Feb 30.


Previous Balance $2582.68
- web site fees     99.00
Current Balance  $2483.68


The club welcomes Sam, a senior at Northgate High School.  Sam will be working
on a model plane for his senior project.

Indoor flying venue.  We will continue at the prior venue.  If anyone knows
of other venues please let everyone know.  George knows a guy who knows
something about the Moffit Field hangar.

If you need a badge, let Ron know.  Needs your name and AMA number.

Christmas party, concensus reached, same time (second Tues in Decemeber),
same place (Buttercups)!


Feb 28, Wagel free flight, weather permitting.


Mike Woodring, two Flite Test Bloody Wonders.

Mike Woodring, Flite Test F22.

Mark Harrison, EZFly. More pics here. Video below.

Mark Harrison, F22.  Notes here. Video below.

Jerry, Sigg Twister.  Finished with orange rustoleum, matching the monokote.

Lee, Ubanko Contest wing, from Ukraine.  Had to order off of Facebook.


bundle of balsa, roll of monocoat, BHM Vulture combat kit, .049 Cox engine, Zap Glue, Interceptor Free Flight kit, 3D Kit Lazer Cut, Roll 0.15x52 flying wires, Solder jig, Screwdriver set, digitial multimeter.



F22 flying around.

blogodex = {"toc" : "CME Minutes"};

Monday, February 9, 2015

CME Minutes, January 2015


Tuesday, Jan 11, 2015

CALL TO ORDER:  7:30 pm


Monthly meeting, Second Tuesday, 7:30 at Concord Airport Terminal.

Friday Fun Fly, Third Friday, 7:00 - 9:00 pm.
Gym at the Church of the Nazarene, 1650 Ashby Dr., Concord

Fun Fly this month on Jan 16.


Over $1100 spent on the Christmas Party. Yippee!

Current Balance $2552.53

Several checks were made out to "CME".  Those were not accepted by the bank.  Checks should be made out to one of the signatories, Ron, Mike, or Chuck.


A great Christmas gathering.  Happy New Year!


Motion: Members in good standing will have dues waived for 2015.
We've got about two years worth of operating expenses at the present time.
Ayes: 11 Nays: 5, motion carries.  Put your money in your pocket!

A membership roster will be sent out to the mailing list.

If you need to be added to the mailing list, send Mark a note:

A service for Bob Andrews was held on Dec. 16.  He was a good guy.

Looking for event ideas at the CL flight circle.  Suggest some!

Idea: Poker flight.  Take a flight and get a card.  Collect three cards, and two cards are drawn at the end.  Best hands get a prize!

San Jose State is looking for a faculty to set up a UAV program.


Watch Discovery Channel's "What Could Possibly Go Wrong?" First or second Saturday in February.  Some members assisted in the production.

PARADE OF PLANES (sorry, no pictures this month!)

Jim Muether: two 1/2A, Searcher and another model.  350 feet altitude in 2.5 seconds.

George Ellison, Black Hawk Polish Fighter.

Steam Boat, Crick kit.  Twin piston engine.

Mark Harrison, experimenting with a "Class C" UMX Radian.

Chuck, Sport Cub, flies nicely and takes off in about 10 feet.


Reno Air Races book, BHM P51 Mustang kit, 1gal Omega 10% fuel, 30m epoxy, 2'' spinner, 1/2'' spinner, BHM SkyMaster II.


blogodex = {"idx" : "CME Minutes"};

Saturday, February 7, 2015

Warren's Balsa Storage

The topic of balsa came up, and Concord Model Engineer Warren Delane shared details on his balsa storage bin.  He writes:

I store my balsa according to thickness in a swing-down bin that is located between joists under my loft.

Bin is made of recycled wood  and swings down from space under a loft between joists. Bottom is 1/8" hardboard. Small chain to restrain further movement. Pivot is black metal pipe, which doubles as pivot for a ladder for access to loft.
Other end of compartment is propped up by a broomstick attached as a handle as weight of compartment with full load of balsa is heavy. Once in place, wooden turnbuckles(?) lock bin from falling.

Crude but effective. I wish for a better system but it works, considering space is very cramped in this end of my Man Cave.

Loft is for storage of covering rolls in Xmas wrap boxes, tissue rolls, disassembled wings and fuselages, and seldom-needed, lightweight stuff. Access is by the ladder on left, made in two sections for compactness.

Pivots down from same black iron pipe as balsa bin. Old TV plays VHS aviation tapes, old hi-fi for FM radio and music cassettes.

Believe it or not, this is as tidy a mess as it gets! Unfinished models are stored in plastic bags and put aside until later. 

 My Man Cave.
10'x12', prefab shed. Strictly for model workshop. A smaller shed (8'x12') is off the the right (OOS) for family storage.
Last time I tried to weigh each sheet on my digital scale and marked the density  near the label, but I had to use a calculator to use in a formula (from the 'net) to get the density. Now, I rearranged the sheets according to increasing density. Of course, thus works only in full sheets. Partial sheets are merely guesstimated.

Close up view of bin in down position. Grooves sawed into top and bottom hold black plexiglas separators for 1/32" and smaller, 3/32", 1/8", 3/16", 1/4" sheets. Last space is for 4" wide sheets. 

Balsa (Equadorian Gold) was hoarded for decades, some sheets date from pre-wartime years! Much of it was salvaged when White Front closed in SSF, a whole display bin for $5!

blogodex = {"idx" : {["balsa", "storage", "workshop", "Warren Delane"]};

Sunday, February 1, 2015

Three F22 Videos

I was chatting with a friend about the awesomeness of the F22s that Andreas built for us, so I thought I would collect the videos here.

Here's the maiden flight, and some notes on how it was built.

Andreas flies his a lot, it may be his favorite plane.  Each time he crashed and broke off a bit of nose, he rounded off the tip a bit.  Shorter, but maybe flies even better!  Here he's painted it and it's a lot more visible.

I crashed mine, but glued the nose back on.  Beacon FoamTac is great stuff!

Share and Enjoy!

blogodex = {"toc" : "F22", "idx" : "FoamTac"};

Friday, January 30, 2015

Some EZFly Pics

 I was going to send someone some close-up pics of my beloved EZFly, the first plane I ever built from scratch that actually flew around.  And I discovered I didn't have any, or at least couldn find them... so off to the bench with camera in hand!
 Stick mounted 1500 kv motor, with 6x3 prop.  Remember, the numbers go forward even in a pusher configuration!
 The rest of the electronics... 12A ESC, OrangeRX DSM2 receiver, and two 9gram servos.
A lot of people fly 1000 mAh batteries, but I've got a lot of 500 mAh batteries for various planes, so generally use those.  2S is fine in still wind, but for me 3S gives just a bit more punch through wind.
 Hot Glue joints work well.  If I were building another, I would switch to FoamTac joints, which are a bit sturder in the long term.
 I used whatever clevis's I had.  Some people have bad experiences with this kind of pushrod connector, but it's worked fine for me.
 To get the CG forward, I had to put the servos way front, and ended up with big giant push rods.  I would try some thinner rods in a new model, although these 3mm tubes have worked well.
A tiny bit of airbrush paint makes the unit a lot more visible.  I've slightly rounded the leading edged, but motorhead's latest revision has a template for chamfered rounded edges.  I should take the time to do that.

Executive summary:  (a) this is a great plane to build, (b) big thanks to motorhead for this great design, (b) check out the RCG thread,  (c) be sure and use the latest R3 plans (on first post in link) which make it easier to balance the CG, (d) good luck and have fun, and (e) let me know if you make one!


  • For a first build, consider buying a kit from designer motorhead at Fancy Foam.
  • I knew I had a reasonable EZFly video!  Here it is flying on 2S.

blogodex = {"toc" : "EZFly"};

Thursday, January 22, 2015

Two Micro FVP Setups for UMX Radian

BWX_@RCGroups has the Ready Made RC Pico FPV Combo (5.8 GHz).

cjz89civic@RCGroups shares his setup here.  It's based on the Flite Test article.

  • Camera $20 This camera is as good as the one that Flite Test uses and there recommended camera is $50 alone.
  • Antenna $9 for 2 (added this I got better video quality and about 100 meters more distance snipped off connector and soldered right to the board as the stock whip was)
  • Dip Switch is a add on its $3 at Radio shack or cheaper on ebay You can simply solder ground to the channel inputs for desired channel to save 1.2 grams.

blogodex = {"idx" : ["UMX Radian", "FPV", "things to try"};

Monday, January 19, 2015

Cartoon SR-71

AJWoods@RCGroups has uploaded a video of a really nifty Cartoon Mini SR-71, and said he'll upload plans before too long.  I think I'll build one!  He reports:
"I have elevons, but the plane could be easily flown as just elevator/diff thrust. Very smooth flyer, a bit less nimble than the F-35, but more forgiving all around (maybe a bit slower too). I designed the fuse profile so that when on the ground the plane makes contact on 3 points with the nose high. This makes for awesome ground handling with no wheels, and allows for ROG takeoffs and touch and go's."
He's got a link to his Cartoon F-35 which also looks pretty sweet!

Here's a video:

blogodex = {"idx" : ["SR-71", "AJWoods", "Cartoon Mini SR-71", "things to try"};

Monday, January 5, 2015

A few video production notes

Here's some notes on making a custom thumbnail for videos.

To extract a single image:

ffmpeg -ss 01:42 -i -vframes 1 foamy-cf-tmp.png

-ss timecode
-i input
-vframes 1   # single frame

Using ImageMagick:

convert -font Helvetica-Bold -pointsize 200 -fill white 
    -draw 'text 50,800 "First Line"'
    -draw 'text 50,1000 "Second Line"' foamy-cf-tmp.png foamy-cf-thumb.png

-font, -pointsize, -fill  specify appearance
-draw 'text x,y "foo"' draws text "foo" at position x,y

blogodex = {"idx" : ["thumbnails","video production"]};

Tuesday, December 23, 2014

EastBay RC joins FAA in encouraging n00bs to fly safely!

Dusted off the NoodleCopter for a bit of late night flying with the KPIX news crew, all in support of  The reporter is Emmy award winner Joe Vazquez.  I thought he was smart, asked good questions, and had a good understanding of the issues involved in flying small aircraft.

There will be quite a few people getting drones, quadcopters, RC planes, etc for Christmas and trying them out for the first time.  If you're one of them, Welcome! We're glad you're here and hope you have a fun and safe time flying.  Check out the rules and guidelines... they're not complicated, they can keep you and your family from getting hurt, and make life easer for all of us if we're all careful not to cause trouble.

If you know of somebody just starting out, point them to some good resources (hint: EastBay RC!) for them to learn.

Couldn't get the video to embed, but here's the direct link:

Saturday, December 6, 2014

HeboCon - The Robot Festival for Dummies!

Two notes:

  • I'm wrapping up a bunch of stuff, will be posting more over the holidays!
  • I so want to compete in HeboCon!

blogodex = {"idx" : ["HeboCon", "funny"]};

Thursday, November 13, 2014

Concord Model Engineers Meeting Minutes, Nov. 2014


Tuesday, Nov 11, 2014

CALL TO ORDER:  7:32 pm

Wednesday, November 12, 2014

EastBay RC Attends DJI Inspire Launch

 So we received an invitation to attend the big DJI product launch over on Treasure Island.  It was an impressive thing... a top not presentation wrapped up by the appearance of the  new "Inspire" unit over the stage.
 It's an impressive unit.  4K video downlinked over DJI's Lightbridge system.  The photo here is of the live video from the unit being downlinked and projected on the screen.
I met Eric Cheng a while back, when he had literally only been flying for two weeks.  Even at that time I had been impressed with his natural flying ability, and of course I'm a big fan of all his photography as well.  It turns out he's a pretty bodacious emcee as well!
 Hey, who are those guys sitting up in the front row?

Yep, it's mythbusters Jamie and Adam.  They've been using multicopters (custom built by their crew) for the last couple of years.  They talked a bit about that, and how the technology has advanced in that time.

Here's a video of the actual product launch.  I guess I can correctly say "literally" here!  It was pretty impressive, and I liked how the legs raise up (or is it the body that lowers?) when it goes into the air? Eric and I are going to get together and do some things with his unit, and I'll collect any useful information.  It looks like a serious contender for filling in the "prosumer" (i.e. not carrying a DSLR) aerial photography market segment.

blogodex = {"toc" : "DJI Inspire"};

Sunday, October 19, 2014

Class Supplies

Here's some good things to get for your OPQ.

Batteries.  Both of these are good.  I will usually buy whichever one is (a) in stock at the USA warehouse and (b) cheaper at the time.

Battery Chargers.  These come in a couple of variations.

DC-only input.  You can make these work if you (a) buy a DC power supply or (b) have an old PC power supply sitting around and are willing to do a bit of connector soldering.  If that's the case, buy some 4mm banana connectors and I'll show you how to do it.

Both of these are similar.  The IMAX brand has a better brand reputation than the Turnigy  brand. I can't quite make out which cables come with the IMAX, but it may be that some extra cables will be necessary from the (tiny) picture.
I've got one of these.  It's basically four of the Accucel-6 chargers in one case.  You need to buy extra power leads, I think it only comes with one set.

AC/DC Input.  These will work with AC wall power as well.

Here's the IMAX with AC input:
Note for the above Hobby King links:
  • these are all links to the USA warehouse.  If you order from the international warehouse shipping is a lot longer.  Make sure you're ordering "USA Warehouse" items if this is important to you.

APC Props

These are good props, but more expensive and only come in a single color. APC props are proudly made in California!  The "P" props are the reverse orientation prop.  The price is per prop, so be sure and order two (at least) of the "SF" ("slow fly") and "SFP" ("slow fly pusher") models.
  • 8x3.8SF
  • 8x3.8SFP
  • I think the 9x4.7SF and 9x4.7SFP sizes will also work but haven't checked them out.

HobbyKing Props

These are similar to the GemFan props.  Lots of colors. 8038, 8045, and 9047 are good sizes.

GemFan Props

Super-popular, these are sometimes hard to find.  A lot of people like them because they're lighter and (the theory goes) will break and protect the motor shaft.

blogodex = {"idx" : ["parts", "opq", "class"]};

"Mod C" Slow Flying UMX Radian

Here's an interesting mod by Rick Rademacher.  It makes the UMX Radian fly almost like a Vapor.  I'm going to try it!

Main Wing

  • obtain three Horizon Hobby Citabria wings (part PKZ3120).  Got mine here.
  • overlap two wings by 3.5 inches.
  • tape the wings together with a strip of tape on each side.
  • insert the wings into the fuse.
  • don't tape the wings to the fuse; the friction will hold the wings in place.
Top Wing
  • cut the third wing in half longitudinally.
  • mount it upside down on the other wings, leading edge forward.
  • lightly tape each side to the other wings
Krueger Flaps
  • use post-it tabs to make krueger flaps on the leading edge.
  • bend tabs to desired direction and shape.
  • vary tabs to match your desired style of flight.

Blogger can't find it, but the howto video is here:

blogodex = {"toc" : "Mod C UMX Radian", "idx" : "UMX Radian"};

Saturday, October 18, 2014

Interesting RC Kite: Preview

Here's a heads-up on an interesting new project. We may be getting some prototypes of a flying kite to test.  I've always thought flying kites were beautiful and I'm excited at the change to try one out!

Preliminary specs for the two three channel models:

1.8m wingspan
motor: 2212 1400KV
battery: 3S, 1300-2200MAH 3s
servo: metal gear 9g
ESC: 20A
prop:  9050

1.0m wingspan
motor: 2204 1400-1800KV
battery: 2S 800MAH
servo: 9g
ESC: 12A
prop: 8043

blogodex: {"toc" : "Flying Kites", "idx" : ["kites", "prototypes"]};

Tuesday, October 7, 2014

EastBay RC Celebrates the Nobel Prize!

Congratulations to Isamu Akasaki, Hiroshi Amano, andShuji Nakamura for getting this year's Nobel Prize in Physics.

“for the invention of efficient blue light-emitting
diodes which has enabled bright and energy-saving white light sources”

Coincidentally a roll of blue LED strip lights happened to arrive on this very day.  Gentlemen, the night-flying RC part of the world salutes you!

blogodex = {"idx" : ["LEDs", "Nobel Prize", "celebration", "rare EastBay Selfie"]};

Nice Foamy LED Mounting

 Not sure where I ran across these, but they've been sitting on my desktop for a while.  A nice simple method of mounting LEDs with skewers and hot glue.

This is a neat idea... the LED shines forward, giving you a light for orientation at the same time that it lights up the propeller.

blogodex = {"idx" : ["Night Flying", "LEDs"]};

Saturday, September 27, 2014

Jack Erbes' BB32 KFm3P Polyhedral Wing

Jack Erbes is one of the modern day geniuses of foamy construction.  Here's his RCG build log of a KFM3 wing for the Blu Baby.  My BB32 wings broke in half, so I'm especially interested in this. I'll lightly edit, but the first person voice is Jack's.  I'll try this later and do my own writeup if I think it might be useful.  Jack writes:

I recently made a KFm2 wing with polyhedral tips for use on my KFoenix Stick and flew it in RET configuration (Rubber, Elevator, & Throttle, no ailerons) and was really impressed with it. It had excellent tracking and control and good rudder authority, which had been a problem with the stock Slow Stick wings. The wing seem to "lean into" the turns nicely as speed increased and as turns were made more aggressively. It was almost as if I were flying a wing with ailerons.

Wednesday, September 17, 2014

decalage -- lots of interesting stuff

Decalage refers to the angle between a plane's main wings and the elevator, or the two pairs of wings on a biplane.  There's a great discussion in the RCG UMX Radian thread.  I'm capturing it here coz... well you know how searching on RCG is.  Post numbers are 3431, 3434, 3435, and 3442. Big Thanks to Phil Alvarez and turboparker for sleuthing these out of the thread.

My Summary:

  • Porpoising is caused by bad decalage.
  • Don't try to solve by changing CG.
  • Small foamies can incur twists due to their light construction.
Standard decalage test:

  • Perform a power-off vertical dive from high altitude (neutralize elevator).
  • A. Model continues straight down: No change needed. 
  • B. Model pulls to canopy: Increase stab incidence with respect to the wing.
  • C. Model pulls to belly: Reduce stab incidence with respect to the wing.

And the words of the masters: