DIY camera intervalometer PCB design

I designed a camera intervalometer PCB. The intervalometer will plug into a camera and control how often and how long and how many shots will be taken.

The PCB consists of STM32F0 microcontroller, TPS63031DSKT power supply switching regulator, which supplys 3V3 for the microcontroller and display from a single li-po cell. Li-po battery is charged through the USB port using MCP73811T charge controller. UI includes 5 navigation buttons and an I2C generic oled display.

The project is in the production state. I will be posting updates when the project is finished.

The pcbs were again provided by PCBWay who offer fast and reliable service. PCBs took 4 days to arrive. PCBs came well packaged. PCBs look good, even the 0402 solder pads are nice quality. The USB connector cutout is nice and square even the inner corners are square. I was happy with the PCB service, mostly by the fast shipping and production time.

You can order your own PCBs here:

2-way Audio crossover

I designed a simple 2-way passive audio crossover, consisting of 2 power inductors and 2 electrolytic capacitors. This makes for a second-order design or 12 dB/octave. This order is commonly used in passive crossovers as it offers a reasonable balance between complexity and response. Higher order audio filters are harder to design, because components interact with each other.

Second order passive filter schematics

I calculated the component values based on the Linkwitz–Riley capacitor and inductor ratios. I chose the cutout frequency to be at 4000 Hz. This value was choosen to better protect the tweeter from lower frequencies.


The pcbs were provided by PCBWay who offer fast and reliable service. Packega came in fast, only taking 4 days to arrive. PCBs came well packaged. On the fist glance the PCBs looked good, the solder pads were nice and sharp. This was the first PCB that I ordered with a silkscreen and it also looked very nice. I was happy with the PCB service, mostly by the fast shipping and production time. You can order your own PCBs here:

Great quality PCBs provided by PCBWay

If this is your first time ordering from PCBWay can also use my referral link: or visit their website:

I sourced all the filter components from Würth elektronik.

Pcb in a reflow owen

Digital wrist watch prototyping

I made a digital wrist watch prototype based around STM32F070 paired with a generic 0.96 inch OLED I2C display. PCB is designed in a way that the OLED display fits the header and mounting holes. The microcontroller uses internal RTC with internal low speed clock oscillator for reading the clock values.

PCB layout

Oled display sits above the main PCB. It features a MCP73871 charge controller which can tel the microcontroller the state of charge and other faults regarding the battery. Two tactile push buttons are used for navigation and the remaing one is dedicated for waking up the microcontroller and oled display. Pcb is designed for use with a TEMT6000 light sensor which has not been implemented yet and will be used for adjusting the oled display brightness. I will be making mre modification to the PCB in the future.

I implemented a code for a simple setting menu.

Super cheap FPV racing drone revisit

Improved pusher racing drone

I recently made some improvements to my previously designed super cheap racing drone. Previous version was converted to a pusher configuration to maximize the cheap electronics performance.

Having the motors in a pusher configuration helps reduce drag caused by a hefty frame. To further improve the design I modeled a new more compact 3D printed canapie which also contributes to improved flight performance. To make the THICC frame even more indestrucable I also 3D printed bumpers mounted at the end of each arm.

Audio amplifier complete design (Tpa3116d2)

Purchase pcbs here:

3D files

Amplifier PCB

I designed a complete enclosure to house my previously designed tpa3116 2x50w amplifier board.

The design includes a 10A fuse to protect the amplifier board in case of a short-circiut or a reverse polarity of the power supply. I also fitted the amplifier ic with a heat sink which help the amplifier to achive the desired 2x50W of output power.

The enclosure is equipped whits several 5mm banana plugs for power transfer and 2 pairs of audio signal jacks.

Simple Contactless hand sanitizer / Soap Dispenser

Automatic hand sanitizer using a 9 gram servo, ultrasonic proximity sensor and arduino nano. The mechanism is very simple using only a string to push down on the cap of the hand sanitizer.

In depth tutorial:

3D print files:

Arduino code:

For further questions feel free to contact me via e-mail.

Tpa3116 2x50w amplifier board design

Purchase pcbs here:

I designed an audio power amplifier board based around the tpa3116d2. I chose the highest possible oscilator frequency of 1200khz. Many chinese designs feature no output LC filter which may result in power losses and lower efficiency. Because of that I chose higher grade components that are included in the output filter. My design also includes a large heat spreder, whitch may come in handy when dealing with a version of the IC that has a bottom mounted heat pad. My design also include loads of vias at the adge of the PCB which take care of high frequency interference.

The ampflifier is capable of delivering 50W to a singe channel load (4ohm).

Gerber files and schematics are publicy avalible on GitHhub.

Super cheap FPV racing drone

Racing drone built for everyone on a tight budget.

Parts list:

  • Frame : Home milled carbon fibre frame – 250mm – 10€ (cost of carbon fibre sheet)
  • Motors: MultiStar V-Spec 1808 – 2400KV Multi-Rotor Motor – 4 x 3,99€ (bought at a clearance sale)
  • Props: KingKong Multirotor Propeller 5×4 – 3,2€
  • fpv drone camera : Foxeer Razer Micro 1/3 CMOS 1.8mm Lens – 14,37 €
  • ESC: 4x – Hobbywing XRotor Multi-Rotor ESC Opto 15A – 4 x 6,47 €
  • Flight controller: F3 Flight Controller Acro 6 DOF/Deluxe 10 DOF – 11,74 €
  • VTX: Eachine TS5828L Micro 5.8G 600mW 40CH – 8,94 €
  • VTX Antenna: Realacc Pagoda Antenna – 3,28 €
  • Reciever: Flysky FS-A8S FS A8S V2 2.4G 8CH Mini – 8,32 €
  • Battery: 3s 1300Mah 60c – 14,57 €
  • 3D printed canapie

The fpv drone price wo. battery is around 95€.

The drone has a 4,5-to-1 thrust to weight ratio. Total weight is about 500g.