Introduction: DIY $25 Oscilloscope

About: I like to learn, like to make, like to share.

Have you ever found yourself troubleshooting a circuit, needing more information than a simple multimeter can provide? If you need to uncover information like frequency, noise, amplitude, or any other characteristic that might change over time, you need an oscilloscope!

Oscilloscopes or scopes are an important tool in the armory of the electronics engineer or tester. They allow you to see electric signals as they vary over time, which can be critical in diagnosing why your 555 timer circuit isn’t blinking correctly, or why your noisemaker isn’t reaching maximum annoyance levels.

The function of an oscilloscope is to be able to display waveforms on some form of display. In the normal mode of operation time is displayed along the X-axis (horizontal axis) and amplitude is displayed along the Y axis (vertical axis). In this way, it is possible to see an electronic waveform on an oscilloscope as it may be envisaged. The waveform could be likened to that of the ripples on traveling along the surface of a pond when a stone is dropped into it.

There are several different types of oscilloscope from analog to digital and more. The first types of oscilloscope were analog, but with the advances in digital technology, most oscilloscopes these days are processor controlled and use digital signal processing to provide excellent displays of the waveforms.

Oscilloscopes are expensive but in this instructable, I will show you how you can make your own portable oscilloscope only at $25.

Watch the video review of the JYE Tech DSO 138.

Step 1: Buying Necessary Components

1. DSO138 Digital Oscilloscope Kit ( buy one from at $20):

DSO138 was designed as a training oscilloscope kit. It contains only the basic oscilloscope functions with no fancy features. Simplicity in structure and easiness in assembly/operation are among the main targets of the design. For this purpose, DSO138 uses mostly through-hole parts. The heart of DSO138 is a Cortex-M3 ARM processor (STM32F103C8) from ST. Its 2.4-inch TFT LCD (320 x 240 dot matrix, 262K colors) displays nice and clear waveforms. Detailed assembly instructions are provided in combination with a troubleshooting guide and schematic. Source codes are also available to allow the user to add their own features. DSO138 is partially open-sourced. This opens the possibility for users to add different features or develop new applications on the hardware. Analog bandwidth: 0 - 200 kHz and Sampling rate: 1 Msps max.

I think it is the best kit for hobbyist because one can learn a lot including when making this.

2. DSO138 Digital Oscilloscope power supply ( buy one from at $2)

This is a dc power supply you can use with DSO. But any wall adapter of 9 to 12 V will work fine.

3. Electric Soldering Iron ( buy one from at $20)

This is a 60W adjustable soldering Iron with a digital display. You can use any 60W soldering iron.

4. 3D Printer (optional) (Anet A8at only $160) (Tronxy X1)

Anet A8 is one of the lowest price 3D printer kits available to buy. You can buy this printer from only at $160. I recommend this printer because it is available in kit form and you can get 3D printer building experience from this kit. The performance of the printer is very much satisfactory. I am using one for more than 1 year and still working fine.

You can also buy Tronxy X1 at only $150. This is also a good desktop printer for a hobbyist.

Step 2: Soldering the Components

This particular scope is both a kit that you can solder yourself and in the end a usable tool. Unfortunately, it only has 1 channel and the LCD screen is rather small. However, for $25, shipping included, it was worth trying. If you’re looking to buy your first DSO and don’t like to spend more, the DSO 138 might just be something to consider.

The kit used two SMD components and come with pre-soldered. All other components are through hole and one can easily solder all the components with the help of the manual comes with the kit. It can be a learning tool for those who have no previous soldering experience.

There is a nice instructable from made2hack you can follow:

You may watch the video also:

Step 3: Using DSO138

Do you want to know how to use this oscilloscope? Jenfoxbot has published an excellent instructable on it. Read it from here:

I added the video link from her instructable. The photos are also taken from there. Thank her for nice work.

Step 4: Printing the Case

Lots of 3D design are available on Thingiverse. You can download any one of them you like. I really like the design by chibikuma2.

The design made by VirtualGentlemen is also nice.

Watch the video based on the design made by chibikuma2.