TFF's FPV test plane build log

[The Flying Farmer]

Im Joshua and this is my first FPV setup.

I wanted a stable plane with plenty of room for separation of the electronics. I might also use it to test an AP setup when I decide on the camera.

This will be a build & question thread of my plane and setting it up for FPV

Post 2 - Wing
Post 3 - Fuse
Post 4 - Tail
Post 5 - Power setup
Post 6 - FPV layout

Thanks for looking and any support provided. Feel free to ask questions and Ill answer them when possible.

TFF

[The Flying Farmer]

Wing

So I started cutting on a sheet of 2mil coro one afternoon and heres the two halves of a wing slid on the spar. The spar is 4 yardsticks. Two butt jointed with a yardstick doubler on each side. The spar is 72". A sheet of coro is 48" so the two halves are 96". I can cut the wing down to whatever ws I want.

WS - 96" to be decided
Cd - 12" plus 2" aileron (may be cut down)

Wing
http://i1232.photobucket.com/albums/ff369/TheFlyingFarmer/8bb1a51b-1.jpg

Some measurements
http://i1232.photobucket.com/albums/ff369/TheFlyingFarmer/b297682b.jpg

Scoring LE fold
http://i1232.photobucket.com/albums/ff369/TheFlyingFarmer/3e039e88.jpg

Hinging ailerons
http://i1232.photobucket.com/albums/ff369/TheFlyingFarmer/f4c0cdd3.jpg
http://i1232.photobucket.com/albums/ff369/TheFlyingFarmer/e628174b.jpg
http://i1232.photobucket.com/albums/ff369/TheFlyingFarmer/13c29402.jpg

Preparing for PU glue with woodpecker
http://i1232.photobucket.com/albums/ff369/TheFlyingFarmer/c58a8d9f.jpg

Glueing Aileron
http://i1232.photobucket.com/albums/ff369/TheFlyingFarmer/7bcd3226.jpg

I slid the spar in and wicked thin CA down spar line, then clamped
http://i1232.photobucket.com/albums/ff369/TheFlyingFarmer/b66465fe.jpg
http://i1232.photobucket.com/albums/ff369/TheFlyingFarmer/327ba620.jpg

I glued on a 5" 4mm wing wrap. I Welder glued a HDPE square for a wing block from the YS to the LE. I then drilled and tapped it for a 1/4-20 thumb bolt for easy wing installation.
http://i1232.photobucket.com/albums/ff369/TheFlyingFarmer/dd7ca73e.jpg


Just for kicks, I like big wings :)
http://i1232.photobucket.com/albums/ff369/TheFlyingFarmer/92ec4f1b.jpg
http://i1232.photobucket.com/albums/ff369/TheFlyingFarmer/1dd0dfbb.jpg
http://i1232.photobucket.com/albums/ff369/TheFlyingFarmer/9c1c9e58.jpg
http://i1232.photobucket.com/albums/ff369/TheFlyingFarmer/5029bdd7.jpg

[The Flying Farmer]

Post 3

[The Flying Farmer]

Post 4

[The Flying Farmer]

Post 5

[The Flying Farmer]

FPV

Current Equipment

Plane:
DragonLink -turnstile antenna
DragonOSD -current, gps, baro/altitude
LM 1.2 1000mW Vtx - cloverleaf antenna
RMRC 540 flight camera
Gopro (internal battery)
1000mAH dedicated fpv lipo to DPCAV Regulator (@12v) to DPCAV LC filter
to be replaced when DT is released: TinyTelemetry for antenna tracker(powered by DL rx with 4.8v flight NICD or 15A bec)

Ground:
Eagle tree GS for diversity
(2) LM Vrx - 9turn helical/SPW antenna
to be replaced when DT is released: EZantenna tracker
Headplays
RMRC aluminum heavy duty antenna tracker
Aurora9 with DragonLink


Layout to come.

[The Flying Farmer]

OK, thats the thread from RCG. Ill be updating it soon:)

[The Flying Farmer]

First Question

For take down, I want all the electronics in the wing so all I have to unplug is the servos.

I know separation is key with my 1W vtx. BUT, I also know you should keep your wire runs as short as possible. SO:
My test plane has an 8ft wing span. How far should I go on the separation of the vtx and DL rx? I think the DOSD will be mounted in the middle. The camera is on the left wing with the vtx. The DL rx and GPS will be on the right wing.
Whats the magic starting distance? I can make wire extension to get the cam and vtx, and the GPS farther away than the cable that came with them allows. But should I?

The DL rx will be about 8" away from the DOSD, but the DL rx antenna will be farther out on the wing.

[airtruksrus]

Separation of the vtx from the rx is fairly vital to preventing primary noise from appearing in the video downlink, as to how much i'm not too familiar with the DL systems. My nitro plane has about 14" separation between the two and would move it out farther is possible.

[aeryck]

IMHO, I think separation is more important than wire length, although others may have different opinions. Especially with a 1W transmitter in the 1.2GHz band, you'll definitely want a lot of separation to reduce interference. Cabling is also an important choice, especially with longer runs.

If you take a look at this thread (http://fpvlab.com/forums/showthread.php?3641-The-Most-Amazing-Invention-Ever-For-FPV), SENTRY has a great wire selection that will help keep unwanted interference out of your cabling runs. Just make sure that you only ground one end of the shielding to avoid a ground loop.

Also, since you are on 1.2GHz, you'll probably want to include a low-pass filter on your vtx to reduce interference on GPS frequencies.

Build looks good, though - Back in the day I had a US AirCore .40 trainer that was built entirely out of coroplast; that thing was about indestructible.

[The Flying Farmer]

Thanks,
aeryck:
Does the lawmate vtx have a low pass filter built in? If not could you please direct me to a quality one? This will eventually be used for crop sensing, and I may have a $6500 camera on board, so I want quality:)

Im 18 and starting a crop sensing service. The gov is doing a lot of research in variable rate and precision applications of nutrients.

[aeryck]

I don't know if the lawmate vtx has filtering already or not, but here is one lowpass filter that should help: http://www.readymaderc.com/store/index.php?main_page=product_info&cPath=11_45_52&products_id=484

[Airborne]

If you are in the US, I would make crop sensing your "hobby". You can't use FPV planes for commercial purposes.

[The Flying Farmer]

Nope, it's donation only.
And for research. I've got the numbers and am getting in contact with the lead professor at MU.

[The Flying Farmer]

I've already bought a couple g's from rmrc. What's $30 lol.

[Airborne]

As soon as it becomes anything other than "you flying it for fun", it's a whole different ballgame. Please see the "LAPD and Realtors" thread here: http://fpvlab.com/forums/showthread.php?3505-LAPD-and-the-Realtors

You should definitely get with your professors and make some calls before you load up on equipment. I am not trying to harsh your mellow here, I'm just letting you know.

To answer your question, no the Lawmate equipment does not include a low pass filter. They are well worth the $30.

[The Flying Farmer]

Update:

http://i1232.photobucket.com/albums/ff369/TheFlyingFarmer/91e2a55e.jpg

Those are 2 yardsticks :)
http://i1232.photobucket.com/albums/ff369/TheFlyingFarmer/31826698.jpg