Quad Voltage Reference

Barbouri has updated his voltage reference board design:


Quad Voltage Reference

This is my version 2 board update, which incorporates supply voltage regulation, over-current protection, and trimmer for the 5.000 volt reference all on the same board.


The new board uses a LM2937IMPX-10, which is a positive linear voltage regulator IC with a 10V output at 400mA in a SOT-223-4 package.

Barbouri has shared project the project on OSH Park:

Vref-4 Version 2.0 ext Pwr


Order from OSH Park

Quad Voltage Reference

DIY Vector Network Analyzer

What to do when a piece of test equipment is too expensive?  Henrik Forstén decided to design and build his own:

Cheap homemade 30 MHz – 6 GHz vector network analyzer

Vector network analyzer (VNA) are used to measure scattering parameters of high frequency circuits

Since I can’t afford even a used VNA I decided to make one myself with a budget of 200€, tenth of what they cost used and about 1/100 of what they cost new

The design files and source code are available on GitHub:



DIY Vector Network Analyzer