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Hey guys, just my first forrey into FPV. I figure I want the simplest and cheapest setup available.

What I want to do is to create a so called "back pack" that consist of a camera and a transmitter to mount on the plane. For the ground station I want to use a simple (read cheap 7" TFT lcd). That way I have a camera mounted on the plane that shows me simple, plain FPV. No OSD or GPS for the moment. As I go on I'll probably add those.

Plane will be the AXN floater from HK.
Radio gear will probably be a 9x with a FrSky setup. I say probably because I'm an optemistic person and there's always the possibility I'll win a million dollars, get bored and hack a multiplex unit. Not a large chance but a chance nontheless.

Here's my FPV setup:
Camera: Sony 420TVL HAD CCD. http://www.ebay.com/itm/New-420TVL-1-3- ... 19c999ca98
It's $20 - cheap.
Screen: http://www.ebay.com/itm/7-TFT-LCD-Color ... 2310e0b64b
%35 with shipping.
Wireless setup: http://www.hobbyking.com/hobbyking/stor ... duct=15295
$60 from HK.

Including shipping and all I'm at $120. Not bad for a first step.
Next up will be my experimentation with antenna setups. Pictures to come!

Bruce has been working on a back pack.. Is yours the same?
João

Very similar concept and execution.

Main differences are:
1) Mine is based on off-the-shelf components and so while being a bit more expensive it's much easier to source.
2) I don't hide my progress and tell others what I'm doing

Too funny.

My fpv setup is EXACTLY the same. Just my monitor is a windows ce pmp with two video sources that can do pnp. (was my old gps system, coolnavi)

Same tx/rx, i made a camera mount out of old aluminum landing gear...

Erazz... have you seen this?? right up your alley. mine too...!

http://www.rcgroups.com/forums/showthread.php?t=1388264

Cheap to build, good performance. Several kinds of configs and how to's.

P.

More useful information on the IBCrazy antennae designs (both clover leaf and skew planar) here:

http://www.rcexplorer.se/page14/CPanten ... ennas.html

I believe this is the antennae design that Bruce is using on his backpack too.

That's the next step.

I have a laser welder at work - I'll try to find some music wire and make a super antenna!

if .035 or .025 mig welding wire will help, I can send you a bunch.

P.

Thanks, I got a large reel too.

I'll probably buy a MIG welder just so I don't feel that I wasted my money

Cloverleaf antenna works like a charm, don't have a set yet, but some guys at our club do, and what a difference!


---
I am here: http://maps.google.com/maps?ll=44.003098,-79.457323

I like your thinkin E, it's a very handy tool to have around. I would try and get a 220v one though. the 110 ones are not good for much more than sheet metal.

P.

So, here's my crack at the antenna.

Impressions? I sat down kinda looking forward to doing it. A bit of relaxation while working. An hour and a half later sporting punctured fingers and croocked eyes I think I don't like these antennas so much... Good new is that if you work slowly and take care you stand a good chance of going crazy but producing a decent antenna.

Steps to build:
1) Go buy 0.8mm copper clad welding wire.
2) Release end from hole of reel.
3) Spend the next 20 minutes reeling back the uncoiled wire and cursing.

4) Cut 3 lengths of wire. They should be somewhat longer than 1 wave length (wl). Since I'm using 5.8Ghz, 1 wl = 52.6mm. I therefore cut 3 pieces that are 75mm long:


5) Bend 3mm off the end - this will be used to "hook" the 3 wires together at the end.


6) Measure 1 wl and add the wire's thickness.
1 wl = 52.6
1 th = 0.8
Bend at wl + th => 53.4mm


7) It should look like this:

(If it doesn't then give up and go do needle point. It get's harder!)

8) Measure out 1/4 wl (and add 1/2 th) -> 13.55 Bend again.


9) It should look like this:


10) And like this after another bend:


11) Still having fun? Doing well? Don't worry, here's your chance to screw it up! Bend the middle piece so the two 1/4 lengths almost touch. Try to keep the angle of bend of th 1/4 lengths at 90 degrees. Sounds easy, no? Well, no. It really isn't easy to do properly and I think this is the first major pitfall.


12) Still with us? Good. You'll make a good masochist. Now hold the base carefully with pliers and bend at 45 degrees. It really doesn't matter at what direction you bend as long as both the tx and rx antennae will be at the same direction. Trying to be clever I went for left hand polarization only to end up with right hand. Go figure.


13) Here's a nice easy step for all you superstitious people. Take off the antenna's plastic cover. Easy. I do good destruction. I'm an engineer!


14) Get out your "helping hands". No, not your wife, this gets hot. Ok, scratch that, you need it to be steady. Screw the antenna into the tx and tape it down. Hold one "petal" to the antenna and solder it into place. You can just "tack" it into place as once the top part is soldered it won't fall apart.


15) Hook the top parts together around the stripped antenna wire (you did remember to strip the insulation, right?)
Once it's stuck together well you can fine tune the shape.


Made it up to here? Good for you. Now you need to do it all over again (4 leaves this time) for the rx.
Who said this is a fun hobby?

Here's a youtube video for the same construction

http://www.youtube.com/user/BMSWEB#p/u/4/FcAqiIKO2XI

Pardon the aussie accent

Spend the next 20 minutes reeling back the uncoiled wire and cursing.

Ok, try this with a 60lb. reel, on top of a 10ft ladder.!!! same thing you just curse more! LOL


Looks good though, he has alternative styles that I think work better for the ground station, but I didn't understand them.

Yeah, I'm using a Skwe-Planar (4 leaf) design for the receiver.

pldb64 wrote:Here's a youtube video for the same construction

http://www.youtube.com/user/BMSWEB#p/u/4/FcAqiIKO2XI

Pardon the aussie accent

You make it look so easy

I can't claim the credit ... but yes - i suspect the author makes it look easier than it may be in practice ... but it was his second attempt and we don't know how many out-takes there were

Yea he makes it look easy, but that's because he skipped the most important step no 3

Not an engineer here. A couple of questions.
1> Does the length of the remaining coaxial matters?
2> It seems to me the 3 or 4 clover leaves are pretty easy to be changed in related angles during transportation. almost need to be pampered for transportation. Does polyurethane interfere with Tx or Rx? My understanding it is not. If not, it seems to me put a ping pong ball like shell aruond the leaves and embed the leaves in a round polyurethane ball will fix those delicate angles permanently. You can bounce it if you want.

Well I haven't damaged them yet... They do seem delicate but as long as you don't sit on them they are fine.


Meanwhile it works. And it's super easy to use. Just turn on and go fly.
I've now found out why you need an OSD.... Almost loosing the model on the first run

Just received my .030" mig wires, ready to get the cloverleaf antenna done. one detailed question about the length of the wire. my FPV TX/Rx has 8 ch to choose from. in the calculator IBcrazy provided, do you have to use the exact frequency you are using or an average number will work for all 8 chs?
what I am trying to ask is if you make one length based on on ch frequency will that work with other chs?

http://www.flickr.com/photos/erezraviv/6773055798/

Hi did you get a good reception with this

These words are from IBcrazy, I can't find the link right now. You can find it at RCgroups.
The most critical part is the length of the wire, the angle is not as important.