Introduction: Star Trek Communicator - FET Tester

By Rick Winscot
About: Has code in brain, soldering iron in hand, Art Blakey blaring in the background... transforms techno babble into reality and is strangely fond of the ellipsis.

You know you're going to blow a FET here and there... when you do - do you have anything to test them with? There are tools out there... like this handy thingy-bob for my multimeter to test transistors.

So... I said 'handy,' not 'pretty.' 

This instructable details an idea I've had to (fu)se (g)adgets, electronic engineering (EE), and Star Tre(k)... or gEEk-fu... to produce a piece of test equipment that will greatly enhance the visual appeal of our shabby-looking workbenches.

There are many great circuits for FET testers on the inter-tubes.

http://www.electronicrepairguide.com/test-mosfets.html

I dropped the schematic in iCircuit and... this is just what we need.

http://icircuitapp.com/

There are also plenty of reference designs for the original Star Trek communicator out there. Spock... can you hear me? SPOCK!

http://www.dreamcheeky.com/star-trek-communicator

What will the FET tester look like? ...and what will it do? Good questions... I've started sketching 2D mockups in Adobe Illustrator for the time being. It will have to have clearance for a half dozen components, a small circuit board, a 9-volt battery, and a bucket of awesome; no problem.

Features on my TODO:

. click on/off potentiometer ( used to drive the FET )
. FET selector switch
. FET selection indicator ( light-pipe P or N indicator )
. FET good / fault indicators ( three LEDs in the center )
. tests N-type and P-type MOSFETS

I'm also toying with the idea to add an ATTiny85 and a speaker into the mix for an audible power-on indicator. Wouldn't that be cool?

Hmm... bad FET huh? Here... let me take a look at that... BEEP BOOP BEEP. Yeah... it's bad.

Let's "Make It Real" and boldly go where no one has gone before. Up-vote this instructable and we can make it happen!