How to make a £9.99 Airwave Vtx module work... for less than a fiver.

[Coyote]

Have you got any videos of this project in action ?

[stevec]

No video yet, I have just got a little mini skywalker that I am going to throw it into for some close in fun, but I don't have any way of recording from my goggles...

I checked the reception in the house and it starts breaking up about  50 feet away with lots of walls in the way. I hope to get out to do a range test in a field soon just to see if flying with a plank is feasible it was originally designed for a quad which by its nature tends to be closer in than a plane.

/Steve


Sent from my iPad using Tapatalk HD

[RogerD]

to make a good kit, an etched PCB with the correct, ie 2mm, pin spacing for the module would be much appreciated by many of us. any one on here do PCB etching?

A quick draft. (Note the IC is really a DIL switch - my software doesn't have DIl switches, but the footprint is the same). I've added a Jumper (J1) for selection of raw 12v or regulated 5v as the power source for the camera).

I could make is tiny with dual sided PCB but it's not necessary and adds complications for some "home etchers". All that's needed now is dragging the header pins to 2mm spacing (from 2.5mm which takes no time) - are they exactly 2mm apart?

[RogerD]

Here is one with 2mm pin spacing and audio pins with capacitors.



Let me know if you want a PDF of the solder artwork (etching stencil). I can make these but it's not really financially viable. I'd be doing it more for fun, but that would wear off quickly :-p

Etching is super simple with a laser printer, some cheap thin paper, and an iron. I did a "instructable" on it.

This, but much simple as it's only single sided. Just lay the design on your copper board and iron on!

http://www.instructables.com/id/Easy-Consistent-Cheap-Toner-Transfer-Method-for-Si/

If I made one I'd do it with the larger 2.5mm pin spacing, and not actually install a 9 pin header. I'd solder 9 wires from the board to the Vtx - less fragile.

[stevec]

This is well cool. I love it.

/steve

[skyscraper]

looks great!

regards
Andy

[Ynot6]

yes, the pin spacing is 2mm. the data sheet is on line (don't know how to do links like that)

[stevec]

There should be a link to the data sheet in the original post.

I think I may have to knock one of these up. looks like I am going to maplin later to buy some etching stuff, never done that before so it looks like fun.

/Steve

[mrwilljackson]

PCB fabrication

http://oshpark.com/ allow you to upload eagle files and will produce low volumes of boards - I used them to to a bruce simpson FPV backpack and they're great. I'd highly recommend them as I ordered three boards, one was faulty, and Laen sent me another three boards foc. You just have to wait for shipping from the US.

I'd never used a service like this and uploaded eagle files which I'd sourced from rcmodel reviews forum btw - I not electronic expert BTW

cheers
Will

[stevec]

Hi Roger could you upload a version of the file that the company in the post above would recognise?
then I will order from them.

Cheers
Steve

[RogerD]

Wow - that service looks great. I'll redo it as a 2 sided board for you. Do you want the pins spaced at 2mm for direct soldering to the Vtx?

P.s I'd still make these myself as it's fun and easy. My Instructable tells you how but the basic process is:

a) Print the pcb design from a pdf onto cheap paper with a laser printer - the type of paper you get supermarket flyers on
b) buy copper pcb board from ebay/maplins - for this board you need about 50p worth.
c) Using an iron, transfer the design to the copper.
d) rub the paper off the copper under a running tap
e) put etching solution (pennies again - either sodium persulphate (clean) or ferric chloride (messy) in a plastic tub
f) put the board in. remove when all the visible copper is gone.
g) wash off toner with nail polish remover (acetone).

Done!

[RogerD]

Well, what a great PCB fab site! - Thanks Will! - Unless I'm missing something, they are somewhat of a bargain! - 3 boards, dual sided, with silkscreen, $10 and free postage. Blimey!

Ok...  Here are two projects. One is dual sided and meant for the PCB fab, or anyone if you can make dual side at home, though there is no need as the single sided version is only a touch bigger as you'll see below.



It is designed for the Immersion vTx to mount on the BACK side, the underside. So components on top, vTx underneath. The pins of the vTx should slide straight into the PCB.

Below is what it will look like when made by the fab linked by Will.



You need the following file to upload to the fab. (not used this file host before so let me know if there is a problem)

http://www.filedropper.com/immers5v

The board ends up being 3cm wide by 4.3cm long - basically a little bigger than the vTx.

OK... next, below is the single sided version. This is designed for making at home if you do your own etching. It's much the same but I've spaced things out to make single sided routing easier.







Above is the copper. I've done it for you in a 1:1 scale PDF below. Make sure in your print options there is no scaling / fit-to-page. This board comes out at around 3.6cm wide by 4.8cm long.

http://www.filedropper.com/5vregforimmersionrc2mmpinspacingsinglemanualv2

[RogerD]

Note:

I HAVE NOT TESTED THIS - use my plans at your own risk. I've checked the wiring at a glance but will give it a thorough checking tomorrow. It's a very simple circuit so it should be OK. (update - just followed every track on the 2 sided pcb and unless I'm missing a glaring error it all seems fine)

The board headers for power, camera voltage selection, audio and video are all standard PCB headers (http://www.ebay.co.uk/bhp/pcb-pin-header). Servo leads plug straight onto these.

The vTx should come with it's own headers spaced at 2mm. these go straight into my board at the top. The end pin marked with "-" on my board is Gnd.

I have marked video "signal" with "s" and GND with "-".

You will need a small jumper to select if your cam wants 5 or 12v. It's positions are marked on the board.

Will - I've never ordered a fabbed board - do the pads come plated through the hole?

[stevec]

Hi Roger, it looked ok to me.
I have ordered 6 from the US site.

came out at about 13 quid!

I'll let you know when they come in.

Roger Pm me your address and I'll send you one for doing the board layout.

(it will probably be several weeks until it happens)

cheers
Steve

[stevec]

Roger,

Is it ok if I add the files you created to my Flitetest article?
I'll make one and ensure it works first but if it is all ok, and I can't see why it wouldn't be it would complete the article nicely.
obviously I will credit you for the design of the board.

Cheers
Steve