This post explains how I built my FPV display, a great tool for bench testing, and it lets others watch your flying in the field. This project requires 3D printing, some cheap components and basic soldering skills.
I spent over a year designing and testing this little device, it was a fun project and I hope you enjoy it as much as I do :)
Table of Content
Features and Specs of DIY FPV Display
You can use any Fatshark receiver module in this FPV display as long as it has buttons to change channels. There are some cheap ones that costs $20 or lower (see parts list for link).
And it has a revolutionary power button! :)
Small LCD monitors available nowadays tend to display a blue screen (or black screen) when signal is gone. This is bad for FPV as we prefer to see static when signal gets low. After some researching, I found a solution.
The work around is simply wiring a DVR between the receiver and monitor. It also provides video recording, so why not? However, you will get OSD from the DVR, and so I added a slide switch which gives you the option to bypass the DVR whenever you want.
This FPV display is powered by 18650 Li-Ion battery, and it can be charged through USB.
There is a battery indicator reminding you when to recharge.
- Battery: 18650 Li-Ion (two connected in parallel, or you can just use one if you want)
- Battery level indicator
- USB charging
- On/Off power button!
- 4.3″ Screen Size
- Supports DVR
- Supports any Fatshark receiver modules with buttons to change channel
- Putting your 3D printer to work :)
- Dimension: 126x96x48mm
- Weight: Around 330g (including Fatshark module and two 18650)
- All the 3D Printed Parts (STL files download): https://www.thingiverse.com/thing:4186909
- 4x M3 nuts (for the case)
- 4x M3 10mm or 12mm screws (for the case)
- 4x M2 3.5mm or 4mm screws (for the screen)
- 3x M3 5mm or 6mm screws (for holding the PCB’s and module bay)
- 2x M3 14mm or 15mm screws (for cooling fan)
- Any Fatshark Receiver Module that is capable of changing channels (I am using True-D V3): http://bit.ly/32sXPuC
- Pin Headers for Fatshark module: http://bit.ly/2MrNFm9
- Unprotected 18650 Li-Ion Battery (I am using Panasonic NCR18650B): https://oscarliang.com/best-18650-li-ion-battery/
- 4.3inch LCD Monitor: http://bit.ly/3clG8Su
- Power switch with LED: http://bit.ly/2SON0wo
- Battery level indicator: http://bit.ly/2HZekoW
- Boost Converter: http://bit.ly/2wTmtcp
- 18650 USB Charging module: http://bit.ly/2wbW8Wh
- 22AWG silicone wires (or larger): https://amzn.to/2VqXBD2
- DVR: http://bit.ly/32wc6a2
- Slide Switch for DVR: http://bit.ly/396PPC0
- Fuse (5A or 7.5A): https://amzn.to/2TgJOw8
- Cooling fan (20x20mm mounting): http://bit.ly/2TeQ6fA
Here are the connections between all the components I used.
I added a fuse for the battery, you don’t have to but it’s good for safety. 5A or 7.5A should do:
- monitor: 0.25A at 12V (<3W)
- True-D module: 0.65A at 5V (<3.25W)
- Eachine Pro-DVR: 0.25A at 5V (<1.25W)
Total amp draw from the 18650 battery (3.7V) should be NO higher than 3A (including fan and battery indicator). Therefore 5A – 7.5A fuse should be enough.
Remove the monitor case.
Unsolder the wires, and keep the three-button controller for changing monitor settings. This is the soldering iron I use.
DC is voltage input, I believe the monitor takes 6V to 32V, and I am going to power it with 9V.
GND is ground.
AV1 is video input 1 which we will connect our video signal to later on.
AV2 is video input 2 but we are NOT going to use it.
Use M2 3.5mm (or 4mm) screws and the little 3D printed holders to secure the monitor in place. Do not over-tighten the screws!
If you don’t want to use screws, I guess hot glue would work too :)
Use M3 5mm screw (or 6mm) and the 3D printed holder to install the voltage regulators like so.
These are boost converters, they can covert lower voltage to higher voltage. Both regulators will be powered directly from 18650 (3.7V). One regulator should output 5V and the other should output 9V.
You can set the output voltage by turning the little knob, confirm output voltage with a multimeter.
And this is how you install the slide switch for the DVR.
Video signal from receiver goes into the DVR, then the monitor. This prevents “blue screen”, and it displays a “snowy screen” when signal gets weak, which is preferred for FPV. With the switch, you can bypass DVR to avoid the DVR OSD whenever you want.
There is a switch cap which you also need to 3D print.
Similar to the voltage regulators, this is how to mount the USB charging board (up side down).
Installing the power button.
Solder silicone wires and fuse to the 18650 batteries in parallel. You can also just use 1 cell if you want, but two gives you much longer run time.
And push the batteries in the holder very gently to avoid breaking the plastic.
There is an LED light on the power button, it’s powered by 9V, hence there are 4 wires.
I labelled the voltage regulators with their output voltages to avoid confusion.
Solder wires to the pin header, which we will use to connect the Fatshark receiver module.
This is the pinout for Fatshark receiver module. It’s universal.
Insert and glue the pin header in the 3D printed module bay. Make sure orientation is correct.
Solder the rest of the components: monitor, DVR, battery indicator, cooling fan, and this is how it looks :) You can now put the housing together.
Insert the M3 nuts in the top housing. It’s a snug fit, align and push it in gently with your finger nail.
Use M3 10mm or 12mm screws here.
Finally, you need to secure the module bay by using a M3 5mm or 6mm bolt.
And that’s it!
Any questions, let me know in the comment or in the forum thread for this project. Happy flying!
There are still some upgrades on my to-do list that I want to add to this display, I will make a V2 when I have time :)