DIY Test Equipment

Click HERE for top level Test Equipment page.

This page captures information about my Do It Yourself (self-made) test equipment. I have been working with, repairing, using, designing/building/testing various types of test equipment for many years. A few of the more recent project successes are listed below:

• One-wire USB thermometer - An inexpensive temperature sensor with a packaged/hardened sensor element used for general laboratory remote sensing. This serial read-out thermometer is based on a COTS 1-wire sensor and an Arduino UNO processor board. Output can be observed using a PUTTY window or via a LabVIEW VI written to display or display/save the 1 message-per-second output. Multiple versions of this sensor have been built and are in regular use around the home laboratory. Details are at this blog post:
  https://qsl.net/n8dmt/1-wire-temp-sensor/index.html 
  
  
• Noise Figure Meter - The current NF meter version covers from 140 MHz to over 4 GHz and is based on SATSAGEN software controlling a ADALM Pluto SDR (or RTL-SDR) receiver with noise on/off controlled over USB to an Arduino + Relay Board interface supplying +28VDC to a commercial NoiseComm noise source. This is a very capable NF system and compares favorably to commercial systems costing well over $1K USD. A follow on project to utilize a far-lower-cost noise source is planned with coverage from 50 MHz up to approximately 2 GHz. Details for the current NF Meter version are at these blog posts: 
  https://qsl.net/n8dmt/rf-noise-source-part-1/index.html
  https://qsl.net/n8dmt/rf-noise-source-part-2/index.html
  https://qsl.net/n8dmt/rf-noise-source-part-3/index.html 
  
  
• LabVIEW RF Power Meter - Have had a spare Mini-Circuits ZX47-55LN RF Detector module in the misc. RF modules box for a while now and having recently sold off my HP/Agilent RF power meters/sensors, wanted to put the little ZX47-55 detector to use as a RF power meter in the home laboratory. Built a functioning RF power meter using the ZX47-55LN sensor interfaced to a computer via a Digilent Analog Discovery 3 interface module and controlled by LabVIEW Community Edition software. Details are at the blog post: 
  https://qsl.net/n8dmt/labview-rf-power-meter/index.html 
  
  
• Stand-Alone RF Power Meter - With the LabVIEW based RF Power Meter completed, the thought to create a stand alone benchtop RF level meter came into focus. The idea was to take a small embedded processor board, add a two line text display, and connect the ZX47-55 to it via an analog interface. Run it off of a wall wart DC (ideally +12V) module, and just plug it in and hook it up to RF when needed. Sounds simple right? The project was a success, with details at the blog post:
  https://qsl.net/n8dmt/stand-alone-rf-power-meter/index.html 
  
  
• RF Comb Generator - The discovery of a commercial RF comb generator module mixed into the lab's RF amplifiers yielded an opportunity to learn about these broad-band non-linear devices. The details of testing and using the commercial version and later building and testing a DIY version are captured in the following blog posts. (The final DIY version works great!)
  https://qsl.net/n8dmt/rf-comb-generators-part-1/index.html
  https://qsl.net/n8dmt/rf-comb-generators-part-2/index.html
  https://qsl.net/n8dmt/rf-comb-generators-part-3-diy-combs/index.html
  https://qsl.net/n8dmt/diy-rf-comb-gen-test/index.html

Will add additional DIY test equipment items as they're created. You, too, can build and use your own test equipment. Give it a try!