The 20x20mm HGLRC Zeus35 has FC, PDB and ESC all integrated into one single board. This powerful little FC is designed with 2″, 3″, 4″ and even 5″ FPV drones in mind, but can one flight controller rule it all?
Check out my FC buyer’s guide if you are new to the hobby.
Table of Contents
Where to Buy?
- Banggood: http://bit.ly/hglrc-zeus35
- HGLRC: http://bit.ly/39AK9QJ
What’s included in the package:
- FC board
- XT30 & XT60 pigtails
- Two capacitors
- Silicone grommets
- Manual
Specs and Features
The Zeus35 is pretty amazing, it has almost everything we need built into a single board!
- F4 FC + 4in1 ESC on a single PCB
- Input Voltage: 3S – 6S
- MPU6000 Gyro
- Supports Betaflight OSD
- 5V 2A BEC
- 16MB Flash Memory for Blackbox
- 2 UART’s
- ESC Rating: 35A Continuous, 40A Burst (10s)
- Supports Current Sensor
- FC Firmware: Betaflight HGLRCF411(HGLR)
- ESC Firmware: BLHeli_S
- Mounting Holes: 20x20mm (M2 or M3)
- Dimensions: 40x32mm
- Weight: 9.8g
Size and Weight
Comparing to a typical 20x20mm FC/ESC stack side by side (Holybro Kakute F7 Mini), the Zeus35 looks bigger. But it’s just one board, with over 20% weight saving.
- 20x20mm Kakute F7 Mini + Tekko 4in1 ESC = 13g
- Zeus AIO = 9.8g
Closer Look at the HGLRC Zeus F411 FC
Right next to the STM32 F411 MCU, is the MPU6000 Gyro. On the same side of the PCB, you can also find the Fortior chips – these are MOSFET drivers for the ESC.
See this post to learn more about how ESC works.
Solder pads are well sized and easy to solder. However there are only 2 UART’s on this board, there is no UART left after connecting Crossfire Receiver (RX) and SmartAudio (VTX). But you can remap the LED pad and S5 (motor output) as softserial pins for other devices.
The solder pads are grouped by function.
On the other side we have pads that are dedicated for the VTX and FPV camera. They even reserved a UART pad for SmartAudio, nice touch.
Here you can either power your VTX with battery voltage (BAT), or 5V.
There’s a boot button too.
Apart from Betaflight OSD and Current Sensor, it also has 16MB flash memory for blackbox logging.
Micro USB Port is reinforced by Epoxy glue.
Flexibility
Having a 35A 4in1 ESC integrated and with the 20x20mm mounting holes, means you can use this board for 3″, 4″ as well as 5″.
It comes with both XT30 and XT60 male connectors, as well as 14AWG and 18AWG wires.
HGLRC also provided two low ESR capacitors of 1000uF and 220uF. These are rated for 35V which should be enough for 4S or even 6S. The 1000uF is for larger quads like a 5″, and the 220uF on smaller builds like a 3″. This is essential for the Zeus35 in order to reduce voltage spikes and power noise, because there is no space for filtering capacitors due to the limited space.
Further Reading: Why adding extra capacitors to FPV drone?
It also comes with rubber grommets for reducing vibrations.
With the rubber grommets installed, you can use M2 hardware to mount the board. If you want to use M3 hardware, simply remove the grommets. and use other solution for soft mounting, such as rubber bobbins.
Installing Zeus35
I replaced the 30x30mm FC/ESC stack in my Holybro Kopis 2 with the HGLRC Zeus35 FC.
It freed up so much space, it’s ridiculous :D The motor wires are messy because they weren’t long enough and I had to extend them. But you can definitely get a super clean build from using this board.
Here’s the pinout/wiring diagram:
Conclusion
The Good
- Super easy to build
- Compact and extremely low profile
- Slight cheaper than buying stack (?)
- Suitable for 3″, 4″ and 5″ Mini Quads
The Bad
- Only two UART’s, but you can remap LED and S5 (motor output) for softserial
- Unconventional PCB size, might be tricky to fit in small frames
- It can be costly to replace if one of the components fails
- Little noise filtering, additional capacitor(s) required on 5″, possibly smaller quads too
For those who have size and weight requirement, might find the HGLRC Zeus FC really attractive. (DJI builds, anyone?)
However, the risk of replacing the whole board when one component fails might be too much for some people. I tried this type of boards before (Racerstar TattooF4S), and I was quite happy with it though it didn’t last long. Only time will tell, but so far the Zeus35 has been reliable (on 5″ freestyle quad). These are worth considering if you are aiming for an extremely low profile build for easy flights, long range and freestyle.
However You do HAVE TO use the 1000uF capacitor, otherwise you will most likely get noise issues, this board has very little filtering built in due to its small size.
Although HGLRC suggests using the Zeus35 on micro quads like 2″ and 3″, it can be difficult to fit inside these small frames as it’s considerably wider than a typical 20x20mm board. Therefore before picking this up, make sure your frame can support this board!
7 comments
I also have 3 of this boards , all gyro noise issue , drone is shaking and giving throtle self , 3 diff builds this same problem
Could you tell me what the 10 unmarked pins on the opposite side of the board are for I’m wondering because one of the motors went out and I just want to use it for a flight controller ..Thanks
I am trying to update the ESC firmware to use RPM filtering but cannot figure out what the correct target is. Is it F_H_40 or maybe 30? I cannot look in the configurator because it auto flashed when I selected the file and I was about to take a screenshot…
Did you switch the firmware on the rx to the fport one?
It says right on the paper for r9mm and fport and I can’t for the life of me get fport to work, even set half duplex and invert and can’t make anything work always end up changing to sbus to fly it, what am I doing wrong?
Please post your questions with more detail on our support forum, we need pictures of your setup and connection.
https://intofpv.com
Unfortunately, the four Zeus35 boards that my friends and I purchased all have the same gyro noise issues (3” with 1404 or 1407 motors, and using the included capacitors), which Mark/UAV Tech found in his review.