kohacraft's blog

Created a High-Loudness ECM Microphone Amplifier that Operates on Phantom Power

I made a microphone amplifier that can run on phantom power and can handle high volume.CircuitCircuit diagramThis is a m...

2021.05.22

Rose

Electronics

Got the PCB I ordered from PCBWay in just six days! and assembled the IV-6VFD clock!

I ordered PCBs for the IV-6VFD clock from PCBWay last week, and they arrived in just 6 days. Here are the details about ...

2021.05.21

Rose

Electronics

Using PCF2129, a real-time clock IC, with ESP32

PCF2129Operates at 3.3VThe PCF2129 is a real-time clock IC that can run at 3.3V, and is connected to the microcontroller...

2021.05.15

Rose

Electronics

All the numbers were displayed by dynamically lighting them with the beautiful and transparent VFD display tube IV-27M

In the previous article, I displayed only one digit, but this time I would like to dynamically light up and display all ...

2021.05.12

Rose

Electronics

Displaying a single digit number with the beautiful and transparent VFD display tube IV-27M

This time I would like to control the IV-27M with ESP32 and display the numbers. Here is the previous experimental artic...

2021.05.12

Rose

Electronics

Shining the beautiful and transparent VFD display tube IV-27M

I lit up the IV-27M, which I bartered with a retro display tube enthusiast in Ukraine. For more information about the VD...

2021.05.12

Rose

Electronics

The 3rd Try My Luck at Buying Unlabeled Junk Famicom Cassettes at a Recycle Shop

This is a section where I buy unlabeled cassettes from the junk Famicom cassette section of Hard Off and try to play the...

2021.05.11

Rose

Famicom

Designed a clock PCB for VFD display tube IV-6 and MM5316N and ordered it from PCBWay

Now that I have completed the clock using IV-6 and MM5316N, I would like to convert it to PCB and order it from PCBWay.H...

2021.05.11

Rose

Electronics

VFD display tube IV-6 and MM5316N clock in alarm clock style

The VFD clock I made the other day was built into an alarm clock to make it look like an alarm clock.The previous articl...

2021.05.11

Rose

Electronics

I made neon tubes glow with an inverter transformer and blocking oscillation

The blocking oscillation circuit is a simple high-voltage generator circuit that can be made using only a transformer, t...

2021.05.11

Rose

Electronics

VFD display tube IV-6 and MM5316N with clock source added to become a clock

In this article, I would like to add a clock source to the previous circuit to make it a VFD clock.The previous article ...

2021.05.11

Rose

Electronics

I made a ring oscillator using transistors

I made a ring oscillator circuit with transistors, where the LEDs light up in sequence.Ring oscillatorIf you connect an ...

2021.05.11

Rose

Electronics

Making a clock using VFD display tube IV-6 and MM5316N

I'm going to make a watch out of an IV-6 that I bartered with a retro display tube enthusiast in Ukraine.Putting the VFD...

2021.05.04

Rose

Electronics

Made a compact DCDC converter that generates high voltage for Nixie tubes from 5V

We have completed a DCDC converter that generates the high voltage required for Nixie tubes from 5V. Here's a look at th...

2021.05.02

Rose

Electronics

Blinking Neon Tube with Arduino

Hi, I'm kohanii.Our shop makes high voltage DCDC converters for Nixie tubes.You can find it at ↓This DCDC converter can ...

2021.05.02

Rose

Electronics

How to convert an Nintendo Famicom to video output super easily with FCAV

Here's how to use FCAV to convert your Nintendo Famicom (NES Japan Version) to video output in a super easy way.The FCAV...

2021.05.01

Rose

ElectronicsFamicomInstruction Manual

Lithium-ion battery-powered compact flashlight I made

By combining a lithium-ion rechargeable battery with an inexpensive charge/discharge board, a compact flashlight was cre...

2021.05.01

Rose

3D PrinterElectronics

I turned on the VFD indicator tube IV-6

I lit up a VFD indicator tube IV-6 that I bartered with a retro indicator tube enthusiast in Ukraine.Here are the detail...

2021.05.01

Rose

Electronics

ESP32 reduced current consumption during DeepSleep by putting HX711 into power down mode.

I configured a scale with HX711 and made a mailbox that notifies me when there is mail. By replacing the regulator with ...

2021.04.28

Rose

Electronics

A retro display tube enthusiast from Ukraine and I exchanged my Nixie tube clock kit for his display tube!

I was contacted by a retro display tube enthusiast from Ukraine. He said he was very interested in alarm clock style Nix...

2021.04.28

Rose

Electronics

Modification of DPS605U, a Chinese regulated power supply with constant current function, almost eliminated the ripple.

When I experimented by connecting a large load to the DPS605U, there was quite a bit of ripple noise on it. Please see h...

2021.04.28

Rose

Electronics

Trying a different step-up circuit to see if a small high current transformer can be used as a power supply for Nixie tubes.

Last time I tried connecting it to the NixieDCDC voltage boost circuit, but it didn't boost the voltage properly, so I t...

2021.04.27 2021.04.28

Rose

Electronics

I got a small high-current transformer, so I experimented to see if I could use it to power a Nixie tube.

I found a transformer that can carry three times more current than the one used in the NixieDCDC, so I experimented to s...

2021.04.27

Rose

Electronics

The LCD panel of the iPhone broke, so I replace it by myself.

The LCD panel of Iphone can be repaired at a cost of about 20US$ if you replace it by yourself. So I tried to replace it...

2021.04.27

Rose

ElectronicsiPhone

ESP32-DevKitC's DeepSleep is consuming quite a bit of current, so I investigated the cause.

The ESP32-DevKitC is a board that makes it easy to use the ESP32.I often use not the Espressif Systems genuine ESP32-Dev...

2021.04.27 2021.04.28

Rose

Electronics

A convenient item that makes the tip of a soldering iron that has become black and no longer soldered shiny

If you use it for a long time or leave it plugged in for a long time, the tip of the soldering iron will turn black and ...

2021.04.25

Rose

Electronics

Added thermometer to NTP calendar & clock of Canon Canola L1211 display

I added a thermometer to an indicator that was manufactured during the short period before the transition from Nixie tub...

2021.04.25

Rose

Electronics

Revenge of buck-boost DCDC converter circuit to operate ESP32 with two batteries

In the previous circuit, when the ESP32 tried to connect to WiFi, the voltage dropped and the ESP32 rebooted. This time,...

2021.04.25

Rose

Electronics

Make a circuit using CH340C for ESP32 writing (success).

The circuit I made the other day could not recognize CH340K on my computer, so I used CH340C to make the circuit.Here is...

2021.04.18

Rose

Electronics

Make a circuit using CH340K for ESP32 writing (failed).

In order to write the ESP32 from the Arduino IDE, a USB serial conversion IC is required. This time I would like to make...

2021.04.17

Rose

Electronics

The NTP calendar & clock was completed by controlling the display of Canon Canola L1211 with ESP32.

Making the clock with a Canon Canola L1211 display unitI would like to make the clock, since the work I have done until ...

2021.04.14

Rose

Electronics

The display of Canon Canola L1211 was dynamically lit with ESP32, and 11-digit numbers could be displayed.

Each segment of the display unit of Canon Canola L1211 can be turned on and off by ESP32Last time, I was able to turn th...

2021.04.14

Rose

Uncategorized

Canon Canola L1211's display unit controlled by ESP32 to display a single digit number.

Each segment of the display unit of Canon Canola L1211 can be turned on and off by ESP32. For more information about JRC...

2021.04.14

Rose

Electronics

Light up the indicator on an old calculator from the 1970s, Canon Canola L1211.

Canola L1211The Canola L1211 was a desktop calculator sold by Canon in the 1970s. It is connected to an electrical outle...

2021.04.14

Rose

Electronics

I bought DPS605U, a Chinese regulated power supply, with constant current function and modified it a little.

The DPS605U is a regulated power supply with a constant current function that can output up to 60V 5A.The four-digit dis...

2021.04.14

Rose

Electronics

The mailbox with a built-in "scale" that notifies me by e-mail when a mail arrives has been completed!

I have completed a mailbox that detects the arrival of mail by weight and notifies me by e-mail.Weighing with HX711Using...

2021.04.14

Rose

Electronics

A very easy way to accurately align the stencil with the PCB

This article is a contribution to PCBWay PCB Design Tutorial.SMD StencilBefore surface mount components can be mounted o...

2021.04.13

kohapepe

Electronics

Make a power supply circuit (step-up/step-down DCDC converter) to run ESP32 on about two batteries.

ESP32 is a microcontroller that operates at about 3V to 3.3V. I'm going to make a DCDC converter circuit to run on about...

2021.04.07

Rose

Electronics

Make a stand to stand the Nintendo switch with a 3D printer

On the back of the Nintendo Switch, there is a small stand that allows you to stand the switch up and play with it. Howe...

2021.04.07

Rose

3D PrinterElectronicsLeaser Cutter

Make a flat light emitting lighting by processing acrylic into a light guide plate with a laser cutter

I wanted to make a plane luminescent light. This is the same mechanism used in the backlighting of laptop computers, whe...

2021.04.07

Rose

ElectronicsLeaser Cutter

Eliminate The noise mixed in with the HX711 readings

I am checking the stability of a scale made with HX711 and a strain gauge, and abnormal values are measured quite often....

2021.04.01

Rose

Electronics

Designed a circuit to automatically switch the power supply from the two power sources (nothing designed to).

I'm designing a battery-powered ESP32-DevkitC. The ESP32-DevkitC can be powered in two ways: from USB or from an externa...

2021.03.31

Rose

Electronics

Designed a power supply circuit to operate the ESP32 with two batteries (actually, I did not design it)

I want an ESP32-DevKitC that runs on batteriesESP32-DevkitC is a board that allows you to use ESP32 easily. ESP32-Devkit...

2021.03.28

Rose

Electronics

Easy Modification Nintendo Famicom Controller USB Kit is now available!

A little over a week after I placed my order, my Nintendo Famicom controller to USB conversion board arrived from PCBWay...

2021.03.28

Rose

ElectronicsFamicom

Sending measurement data to Ambient to check the stability of strain gauge "scales".

I would like to leave the "scale" I made the other day outdoors for a few days to check the fluctuations in the readings...

2021.03.27

Rose

Electronics

See if I could measure the correct weight with a "scale" made from a strain gauge.

I did an experiment to see if the "scale" and the program I made the other day could measure weight correctly. Here's th...

2021.03.27

Rose

Electronics

Make the PCB that can be used with Nintendo Famicom controllers for a PC from PCBWay.

I want to play games with an Nintendo Famicom controllerWhen playing on a PC with an emulator such as NES, you will be p...

2021.03.27

Rose

ElectronicsFamicom

Making a mailbox with a built-in "scale" to let you know when the mail arrives.

If your mailbox is outdoors, you will not know if your mail has been delivered. Often, we don't even notice for a while ...

2021.03.21

Rose

ElectronicsInstruction ManualLeaser Cutter

Modify the circuit of the HX711 module to operate at 3.3V and measure the weight with ESP32

HX711 module is 5V specificationThe HX711 module sold on Amazon is designed to work with a 5V power supply. Since the ES...

2021.03.21

Rose

Electronics

GPS Nixie tube clock that looks like an alarm clock

I assembled two Nixie tube clocks with GPS in the form of alarm clocks.In this article, we are assembling the product he...

2021.03.17 2021.04.18

Rose

Electronics

How to use the GPS-equipped e-paper clock.

Apply powerPrepare a USB charger at home or a USB charger sold at a 100 yen store. Plug the USB connector into the USB c...

2021.03.10 2021.03.17

Rose

Electronics

How to set the time zone of the GPS-equipped e-paper clock

Learn how to set the time zone for your GPS-equipped e-paper clock. You will need a smartphone to set this up.The e-pape...

2021.03.10 2021.03.17

Rose

Electronics

GPS e-paper control PCB is placed in a photo frame and GPS e-paper clock is completed.

In this project, I would like to integrate the GPS e-paper control PCB into a photo frame and make it into a GPS e-paper...

2021.03.10 2021.03.17

Rose

Electronics

Made the e-paper control PCB with GPS function.

I made a control board for an e-paper that has a GPS module and can keep accurate time at any time.Printing solder paste...

2021.03.10 2021.03.17

Rose

Electronics

JLCPCB charges for the same design panelizing

In the past, JLCPCB did not have to pay extra for imposition of two exactly the same circuits on a 10x10cm board, but wh...

2021.02.15

Rose

Electronics

Stamp with the CO2 laser cutter EtcherLaserPro.

When you use a laser cutter to make a stamp, you usually use silicone rubber.This time I would like to make a stamp by c...

2021.02.06

Rose

Leaser Cutter

Make a wooden key chain by engraving and cutting with CO2 laser cutter

I made a key chain from MDF and veneer, engraved & cut with EtcherLaserPro.Preparing the processing dataFirst, convert m...

2021.01.10

Rose

ElectronicsLeaser Cutter

Record the sound source of the actual Nintendo Famicom in stereo [MOTHER]

MOTHER spoiler alert?Hi, I'm kohanii.This site sells a kit to turn your Nintendo Famicom into a pseudo-stereo system.Thi...

2021.01.10

Rose

Famicom

How to fix a Bose QuietComfort QC25 that has lost sound on one side for about $30.

Do Bose NC headphones have a tendency to break the speaker on one side? Two of them brokeI have two QC25s, and one of th...

2021.01.02

Rose

ElectronicsInstruction Manual

I made a dynamic microphone with the speaker unit of headphones! & I also tried it with ordinary speakers!

Hi, I'm kohanii. In the following blog, I had repaired the speakers of the Bose QuietComfort QC25 headphones. When I rep...

2021.01.02

Rose

Electronics

How to distribute video to Windows 10, Mac, Android in LAN with OBS Studio

Hi, I'm kohanii.Introducing how to distribute video from a webcam or other device to another PC, Android, etc.Setting up...

2021.01.02

Rose

ElectronicsInstruction Manual

Make the large 8x8 LED dot matrix even brighter

Hi, Konanii here.It's Halloween today.I made a Large 8×8 LED Dot Matrix before.The resistor attached to limit the curren...

2021.01.01

Rose

Electronics