I am very new to the multicopters hobby and a super newbie to the FPV (First Person Viewer) flying. I’ve never watch in real time someone flying through the screen but I’ve watched hundreds of videos online! The best-case scenario is to use some goggles (like the Fat Shark) in order to have a better experience. This will make you believe that you are actually inside the cockpit flying the machine. And that’s awesome!
But sometimes, even when everything looks simple this is not translated to cheap as well! A good FPV system, from the camera on the copter to the radio transmission system and the screen on the ground will cost you sometimes more than $200 (without even taking the price of the goggles into the equation). This is huge for my budget especially when the cost will be mirrored to a hobby of mine! So, I am going to try the most efficient solution!
To begin with, I have to order a few components! It seems that the most cost effective transmitters are in the 5.8GHz range. This frequency is more than great when you have visual between the two antennas. But as you go behind a wall or a tree or a dance object in general, then the problems will start. I don’t care about that for my first FPV system and that’s why I’ve selected the SkyZone/Boscam 200mW 5.8GHz combo packet.
This comes in a white box and inside you will find everything.
The RC305 receiver and the 200mW transmitter
As well as, all the peripheral cables for powering the system and sending the video signal
The quality seems nice on the touch. Everything is shiny and well build for the price I’ve paid! This combo packet has also very good reviews from other users out there, except for those things
Those are some linear polarized antennas. You can find them under lot of names like stick antennas, pen antennas etc. And there are two problems with those. First the quality of the particular ones is not good. Second, the technology of this type of antenna will not work into something that bangs and turns constantly.
I decided to spend a little bit more and go with something like those
They are circular polarized antennas into the 5.8GHz band and are made from ImmersionRC. They are calling them SpiroNET antennas and the build quality is amazing! I don’t have a network analyzer (or a spectrum analyser) to test them but they claim that they test every single one before shipping (and I am a little bit skeptical with that). The dome that covers the antenna will help prevent the wire loops from bending during crashes. A must have feature for a newbie!
And if you wondering how they are from the inside then have a look at the photos below
As I said above, very good build quality that is expected from a company like them! Be aware though! The SpiroNET antenna combos are coming in SMA and RP-SMA versions. For the SkyZone/Boscam combo used above will accept only the RP-SMA type
And now the camera! It seems that everyone is using Sony Super HAD CCD camera. They are saying (the internet) that this is the best thing you can buy out there and they are 100% correct. It is amazing! Small, light and handles the rapid light changes very good. It also goes with a very good price tag. Around $25, including shipping, depending on the lens that you want
The camera declares that is a 600TVL (Television Lines) and thats pretty good for an FPV system. Of course is just a bare camera with no enclosure at all. But this what you want! Every gram counts in a multicopter system.
Connecting the cables and you have a working transmitting system. Here, I am using an older black and white camera but putting the Sony one is easy as unplugging the one cable and plugging the other one
The other side of the system consists of the 5.8GHz receiver and a cheap eBay LCD. You can find this LCD model for around $30 but if you are patient and try a bidding process then it can go as low as $15, including shipping. And that’s what I did! It came to my door the other day (after a waiting period of something like 40days) with just fifteen bucks. Pretty amazing!
The box was slightly hidden on the sides but the internals were untouched
Inside the box there are a few cables, a stand with adhesive, a small remote that includes the coin cell battery and a nice tray that will help put the screen on an enclosure or something similar
I’ve made a small teardown of the LCD to discover more or less what I was excepting. Nothing more than the LCD panel and a small driver board
And this emptiness under the screen’s hood is good! The dimensions are looking nice… So, I can fit the receiver in there together with a video recorder (that I don’t have for now). But before any actual “hacking” first I have to be sure that everything can come together easily
I tear down the RC305 receiver as well to check the internals and the actual dimensions of the PCB
The PCB looks good dimensionally wise and can fit easily inside the screens plastic covers. Actually it leaves so much free space for even a second receiver, a video recorder or a diversity circuit with two antennas that I may design and build later!
The LCD panel metal cover is conductive and I’ve used a small piece of cardboard taken from the actual shipping box of the screen. I am going to secure that in place first with some small strips of clear tape and then with high temp hot glue. With that way it will stay in place securely without any problem due to the components heat
I’ve marked the antenna position by measuring distances with a ruler and then use a small drilling bit to do the first inspection hole. By doing that I can adjust the position of the drill in case the alignment is not as I want
Then, after the initial inspection of the alignment a bigger drill used to make the final hole that fits the RP-SMA connector almost precisely!
And now its time for some soldering. First, I’ve used the “beep” function of my multimeter to locate all the connections and then noted them of the metal LCD cover
The connections are: Power, GND, Video IN 1, Video GND, Video IN 2 and Audio. To be honest, I am not 100% sure about the last one (the Audio) but I am not going to use it anyway. This screen does not come with an internal speaker or a speaker output as well. I can recognize some circuitry for an audio interface but due to cost savings they didn’t include the speaker. I will investigate even further later and possibly I will include a cheap speaker or a 3.5mm jack for headphones
Then the receiver received the “hacking” treatment! I removed the connectors and marked the pins that I wanted. Later on I’ve cleaned all the surfaces that I was previously desolder in order to have better connections, reduce strange couplings due to the residues and… because I wanted to look prettier!
Next, some wiring between the receiver and the driver board of the screen. I’ve start from the video connection all the way to the power ones. Both of those can be powered from the same voltage level and a 3S LiPo battery is a nice fit
More hot glue to secure the cables and all the other bits and pieces and here we are! A working FPV system for a fraction of an already made one with the same specs!
But I had to make some final touches! First a XT60 connector for easy plug and play with the battery
Then because the receiver uses a liner regulator (a no name 7805 in SMD form factor) it produces lot of heat. I am going to replace this energy consuming devise with something switching (and low noise of course) but for now I make the missing speaker holes a bid wider for better air circulation
Finally I needed a sunshade! You can find one online for something like $15 – $30 in different sizes and materials, always including shipping. I don’t know what is the best fit for my needs and that’s why I am going to build one for now
A piece of an old HP printer box has used.
Some cuttings, a little taping and then folding and the initial idea is taking shape
Then to add durability and strength I’ve used some aluminum foil tape to cover the top surface of the sunshade. I don’t want to do that on the bottom side because of the reflective properties of this tape.
Together with that, I add strips of clear tape around the tips of the shade. This will prevent your fingers from cuts. Some velcro strips will hold the shade in place.
And to make it prettier and break the monotony of the color I add some Dangerous Prototypes stickers. I received those with a PCB order I’ve get some weeks ago
So, what you think? You like it or not? What I should include for the next version what I have to change? For any suggestions write a comment below or send me a mail at: firstname.lastname@example.org
More photos of the project here