DIY Miniature and Wearable Electronics


MiniWear – DIY Miniature And Wearable Modules That Can Be Worn Anywhere On The Body. James Cannan writes:

We love electronics, especially Wearables, and that is why we have made super cool modules that include heart rate detection, movement, non contact temperature sensing, and ultraviolet (UV), infra-red (IR), and light sensing technology. We are also one of the first in the world to have combined our modules with a variety of open source 3d printed cases, which will take your projects to a whole new level!

DIY Miniature and Wearable Electronics – [Link]

NE555 timer sparks low-cost voltage-to-frequency converter


by Gyula Dioszegi @

In 1971, Signetics—later Philips—introduced the NE555 timer, and manufacturers are still producing more than 1 billion of them a year. By adding a few components to the NE555, you can build a simple voltage-to-frequency converter for less than 50 cents. The circuit contains a Miller integrator based on a TL071 along with an NE555 timer (Figure 1). The input voltage in this application ranges from 0 to –10V, yielding an output-frequency range of 0 to 1000 Hz. The current of C1 is the function of input voltage: IC=–VIN/(P1+R1).

NE555 timer sparks low-cost voltage-to-frequency converter – [Link]


JFET Moving Coil (MC) Pre-Preamp Kit


by Mark Houston @

I received the Boozhound Labs JFET Moving Coil (MC) Pre-Preamp Kit a while back and I promptly assembled the small circuit board. I’m a sucker for a simple kit and a hot iron. That is where it all stopped. The circuit board remained complete and laying about for a few years. Recently I required another MC stage because the tube moving-magnet (MM) preamp I had just completed did not work all that well with the Jean Hiraga MC stage I had been using for years. It appeared the Hiraga had too much output and was over-driving the tube stage. So I needed another MC stage.

JFET Moving Coil (MC) Pre-Preamp Kit – [Link]

Miniscope v2f


Here is another variant (after miniscope v2a, b, c, d, e) of simple PC/USB oscilloscope/recorder:

It extends miniscope v2e with PGA (MCP6S21) offering same sampling frequency (480 ksps, 8 bit real time streaming to PC allowing continuous recording up to 512M samples) but 8 gain ranges and high input impedance. Estimated price is $6 – $7 if using homemade PCB (single sided, 1.35 sq inches).

Miniscope v2f – [Link]

WiFi-based Weather Forecast and Clock



This project is a stopgap on my way to building a ground-up “Internet of Things” base design around the ESP8266 SoC WiFi solution. I started by taking a few nixie tubes I’ve had lying around from a past project, and connecting them to a Nixie Power supply I found on ebay. After making sure they lit up, I wired the Nixies up to a HV5622 chip (which anyone who makes Nixie clocks should really consider for their designs).

WiFi-based Weather Forecast and Clock – [Link]

Attiny45 EMF Sensor


by Khaleel123 @

This sensor is very sensitive and can pick up electrical signals from anything that uses power. It displays the amount of interference it picks up by sequentially lighting 4 led’s one after the other. I have tested it all around the house and its been kinda fun to see how different things compare. It can also be used to follow house electrical wiring inside the walls, yes its that sensitive.

Attiny45 EMF Sensor – [Link]

EEVblog #796 – Leica DVM6 3D Microscope

Dave checked out the Leica DVM6 3D microscope at the Electronex 2015 stand.
It’s an $80000 microscope that can do automated 3D surface mapping and measurements of surfaces, down to sub 1 micron.

EEVblog #796 – Leica DVM6 3D Microscope – [Link]

Transparent ESP8266 WiFi-to-Serial Bridge


jeelabs @ has written a firmware for ESP8266 that enables it to talk to RS232 of your mcu via WiFi and also programm your mcu via WiFi. He writes:

This firmware connects an attached micro-controller to the internet using a ESP8266 Wifi module. It implements a number of features:

  • transparent bridge between Wifi and serial, useful for debugging or inputting into a uC
  • flash-programming attached Arduino/AVR microcontrollers as well as LPC800-series and other ARM microcontrollers via Wifi
  • outbound TCP (and thus HTTP) connections from the attached micro-controller to the internet
  • outbound REST HTTP requests from the attached micro-controller to the internet, protocol based on espduino and compatible with tuanpmt/espduino

The firmware includes a tiny HTTP server based on esphttpd with a simple web interface, many thanks to Jeroen Domburg for making it available! Many thanks to for contributions around the espduino functionality.

Transparent ESP8266 WiFi-to-Serial Bridge – [Link]

Building our own backup server using the Raspberry PI


by Michal Remias @

We’ve been always thinking about building our own backup server using the ARM solution of Raspberry PI. When we needed to manage approx. 25 WordPress web projects couple of months ago we did some experiments with MainWP on virtual server at DigitalOcean.

To make the server a bit more reliable and stable, we decided to add a standalone power supply and a bit of intelligence to the whole solution. The additional components are not necessary but will help you to keep the server running even in the case of short power failures which could lead to damage of the backup files and errors in database.

Building our own backup server using the Raspberry PI – [Link]


Bias generators with ultralow noise and ripple for sensitive circuits


The LT®3095 generates two low-noise bias supplies from a common input voltage ranging from 3V to 20V. Each channel includes a fixed frequency, peak current-mode step-up switching regulator and a low-noise, singleresistor- programmable 50mA linear regulator. The linear regulator’s high power supply ripple rejection (PSRR) combined with its low-noise performance results in less than 100μVP-P output ripple and noise.

Bias generators with ultralow noise and ripple for sensitive circuits – [Link]