Showing posts from August, 2019

Raspberry Pi Remote Site VPN Client Gateway

I need to be able to manage some remote systems to help maintain some remote radio stations. Here's the basic of how to setup your own. This will allow you to connect to computers behind the router without having to setup a static IP address. This post assumes that you have a reasonable understanding of how to navigate directories, copy, and edit text files from the Linux command line. Requirements Raspberry Pi (2 B+ or better) Micro SD Card  Power supply Ethernet or Wifi Internet connection Screen with HDMI input Cable from HDMI to screen's input HDMI to VGA, HDMI to DVI, or HDMI to HDMI. VPN Server/Service We'll assume that you either have an Open VPN server setup or subscribed to an OpenVPN service. Steps to Setup Raspberry Pi VPN Client Gateway Create your SD card to run your operating system from. I chose the Raspberian Lite from Install the card, connect the peripherals, and power it on. Login

Lab Tools, Supplies & Reviews

In this post I'd like to share what I use in my lab. Items with and asterisk (*) are items that you really need to operate a basic lab. Tools Power Supply: Dr. Meter PS305DM 30V/5A DC Bench Power Suply Single Output 110V/220V Switchable *Volt Meter: Southwire Tools 16040T Compat Auto Range TrueRMS Multimeter I bought this locally at a building supply store. It has bluetooth but I haven't been able to connect to it with my phone yet because of OS version incompatibility. I really like the tester and the fact that it auto sets the size. The leads are nice but it would be nice to have some alligator clips on the ends so I purchased some push on alligator clips separately.  Here *Soldering Iron Weller ? Watt I've been using this for quite a while and it works reasonably well. I like the LED's though they are a little dim. My biggest complaint is that the tip has worn out very quickly. I like

Wemos D1 Night Light

Objectives: Build a circuit and program that responds to the environment. Parts Wemos D1 Photo Resistor 10K Resistor Directions Clone https://githubcom/awoehler/ Open Examples/NightLight/NightLight.ino Connect the 3.3+V to the photo resistor. Connect the photo resistor to a 10k Ohm and connect it to GND. Connect the line between the photo resistor and the 10k resistor to the A0 on the Wemos board. Compile and upload the sketch to the board.  Exercises Adjust the threshold values to work better for your environment. Change it so that as it gets darker the light get's brighter. Add a brighter light.

Wemos D1 Push Button

Objectives: Build a circuit and program that allow you to control when a light turns on and off. Parts Wemos D1  Switch Directions Clone https://githubcom/awoehler/ Open Examples/ButtonLight/ButtonLight.ino Connect one side of a button to D3 and the other side to GND. Since D3 and D4 have built in resistors we don't need to add any other items to make this circuit work. Compile and upload the sketch to the board.  Exercises Change the program so that the button toggles the light on and off.

Wemos D1 Blink

Blink is a simple program to get you started with our ESP8266 and the Arduino IDE. Objectives: Learn how to interact with the built in LED. Learn how to use the serial monitor. Parts Wemos D1 Directions Clone https://githubcom/awoehler/  Open Examples/Blink/Blink.ino Compile and upload the sketch to the board. Open then Serial Monitor and make sure that the board rate is set to 115200. Press the reset button on the Wemos and you should see Begin followed by off, on, off, on, ..... in the serial monitor. Exercises: Add comments explaining what each line of code does.  Change the blink pattern to transmit an SOS signal in morse code. 

Getting Started with your Wemos D1

The easiest way to get started is to clone  and the open up the examples and work through the problems. Download the latest version of the Arduino IDE from Add, to your Additional board manager in preferences. Go to Tools -> Boards -> Board Manager Type wemos in the search bar and press search. Find the esp8266 by ESP8266 Community and install it. Connect your Wemos D1 USB port to your computer. From the Tools -> Board menu select LOLIN (WEMOS) D1 R2 & Mini option. Next make sure to tell the Arduino IDE which serial port the Wemos is connected to by using the Tools -> Ports option. Now you are ready to get started with the Wemos D1 Series Parts: Wemos D1