Arduino Transistor Identification and Transfer Curve Tester - Part 2

Arduino Transistor Identification and Transfer Curve Tester RelayBoard

In part 1 of this series, we reviewed the block diagram and discussed the additional chips that I used for my Arduino based transistor identification and automated test tool.  In this article, we will look at the wiring diagram.  There is no critical wiring or timing path, so any of the common prototype or point-to-point  wiring boards will do.
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Sansui 771 Stereo Receiver 35 year long term product review

Sansui 771 Stereo Receiver 35 years young

My Sansui 771 Stereo Receiver has now been with me for 35 years.  It continues to be my primary amplfier and it deserves a long term ownership product review.
I purchased this receiver in "used" condition in 1978.   Other receivers and amplifiers have come in to the shop to challenge it's position, but it has remained in the #1 position.  Why does it sound so good and why do I like it so much?

Top 10 Drupal web site backups best practices

A rule I follow is that when you need to use a backup, you probably will need it very badly.  Here are my 10 best practices for setting up Drupal site backups so that when (not if) the day comes you need to do a restore, you will be able to recover with minimal downtime and impact.
#1 : Name  a person (not a team) who is personally accountable for monitoring the backup process.    This doesnt mean that person is doing the backups or fixing the process if it breaks down, but it is that persons job to ensure that alerts from backups are resolved and has tribal knowledge of how the backup process works.  
Click read more for Best Practice #2 to #10 ...

Arduino Transistor Identification and Transfer Curve Tester - Part 1

At, we have a lot of transistors collected over the years.  Many are unmarked and we are not always sure if the device is functional or has sufficient gain for our projects.  Our solution was to build an Arduino based test device that wil positively identify each lead, the type (PNP vs NPN), material (Silicon or Germanium), and then collect enough data points for us to determine the gain and DC transfer characteristics. 

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